 
Practice Using Toolkit Applications Hands-On Lesson (Python)
===========================================================================
 
   May 21, 2018
 
 
Note to SpiceyPy Users
--------------------------------------------------------
 
   SpiceyPy users need to install a CSPICE toolkit to make SPICE toolkit
   applications, which are not included in SpiceyPy, available on their
   computer. This lesson assumes that they have done so and references
   application executable and documentation locations as provided in the
   CSPICE Toolkit.
 
 
Overview
--------------------------------------------------------
 
   In this lesson you will practice using some of the application programs
   provided in the Toolkit -- ``brief'', ``ckbrief'', ``spacit'',
   ``commnt'', ``toxfr'', ``tobin'', ``chronos'', ``states'', ``spkdiff'',
   and ``frmdiff'' -- by completing a series of simple assignments for each
   of them.
 
 
Note About HTML Links
--------------------------------------------------------
 
   The HTML version of this lesson contains links pointing to various HTML
   documents provided with the Toolkit. All of these links are relative
   and, in order to function, require this document to be in a certain
   location in the Toolkit HTML documentation directory tree.
 
   In order for the links to be resolved, if not done already by installing
   the lessons package under the Toolkit's ``doc/html'' directory, create a
   subdirectory called ``lessons'' under the ``doc/html'' directory of the
   ``cspice/'' tree and copy this document to that subdirectory before
   loading it into a Web browser.
 
 
References
--------------------------------------------------------
 
 
Tutorials
 
   The following SPICE tutorials are referred to by the discussions in this
   lesson:
 
      Tutorial              Contents
      --------------------  -----------------------------------
      Intro to Toolkit      lists all Toolkit applications and
                            provides their location within the
                            Toolkit
 
      Toolkit Applications  provides an overview and a small
                            example for most of the applications
                            covered by this lesson
 
      SPK                   provides additional information for
                            ``brief'' and ``spacit''
 
      CK                    provides additional information for
                            ``ckbrief''
 
   These tutorials are available from the NAIF server at JPL:
 
      http://naif.jpl.nasa.gov/naif/tutorials.html
 
 
User's Guides
 
   The Toolkit includes a User's Guide document for each of the application
   programs provided with the Toolkit. The plain text versions of the
   User's Guides are located under the ``cspice/doc'' directory in the
   Toolkit installation tree. These documents have the same names as the
   application programs with extension ``.ug''. For example, the User's
   Guide for the ``brief'' program is ``cspice/doc/brief.ug''
 
   All User's Guides are also included in the Toolkit in HTML format. The
   index page providing links to the HTML User's Guides is accessible using
   the ``User's Guides'' link on the top level HTML index
   ``cspice/doc/html/index.html''.
 
 
Recommended Setup
--------------------------------------------------------
 
   None of the Toolkit programs used in the this lesson are GUI
   applications. All of them are either command line programs or
   interactive programs that use simple textual prompts or menus to get
   user inputs and directions. For this reason these program must be run
   from a terminal window on Unix platforms and from a command window on
   Windows platforms.
 
   All of the examples included in this lesson assume that the programs can
   be run by simply typing their name on the command line. To be able to do
   that the location of the Toolkit executables directory ``cspice/exe''
   must be added to the system's environment variable ``path''.
 
   On a UNIX system you can add it using the ``set'' command as follows:
 
      set path = ($path /my_directory/cspice/exe)
 
   where ``my_directory'' is the name of the directory under which the
   Toolkit is installed on your computer.
 
   On a Windows system you can add it by changing the environment variable
   ``PATH'' from the ``Advanced'' pane on the ``System Control'' panel to
   include:
 
      drive:\my_directory\cspice\exe
 
   where ``drive:\my_directory'' is the name of the directory under which
   the Toolkit is installed on your computer.
 
 
Kernels Used
--------------------------------------------------------
 
   The following kernels are used in this lesson:
 
      FILE NAME                      TYPE  DESCRIPTION
      ------------------------------ ----  ------------------------
      dii_sc_050112_050703.bc        CK    DII pre-separation CK
      dii_sc_050703_050704.bc        CK    DII post-separation CK
      08110_08152pl_live.bc          CK    Predicted CASSINI CK
      08132_08137ra.bc               CK    Reconstructed CASSINI CK
      di_v17.tf                      FK    DI Frames Kernel
      cas_v40.tf                     FK    CASSINI Frames Kernel
      naif0008.tls                   LSK   Generic LSK
      dii_sclkscet_00008_science.tsc SCLK  DII SCLK
      cas00137.tsc                   SCLK  CASSINI SCLK
      di_finalenc_nav_v3.bsp         SPK   DIF Encounter Opnav SPK
      dif_preenc174_nav_v1.bsp       SPK   DIF Long Radionav SPK
 
   These SPICE kernels are included in the lesson packages available from
   the NAIF server at JPL:
 
      ftp://naif.jpl.nasa.gov/pub/naif/toolkit_docs/Lessons/
 
   All examples in this lesson assume that these kernels are located in the
   directory from which you will run the programs. If you use kernels
   supplied in the lesson package, arranged under the
   ``kernels/<kernel_type>'' directory tree, you can copy them to your
   current directory by typing this command on your Unix computer:
 
      % cp [path_to_lesson_dir]/kernels/*/*.* .
 
   or this command on your Windows computer:
 
      % copy [path_to_lesson_dir]\kernels\*\*.* .
 
   where ``[path_to_lesson_dir]'' is the path to the directory under which
   the lesson package is installed.
 
 
Note About ``Screen Shots'' Included in This Lesson
--------------------------------------------------------
 
   To fit into the 60-character width used for the example ``screen shots''
   included in this lesson the application command lines and user responses
   to application prompts were wrapped at the 60 character boundary (to
   preserve all required arguments and responses) while the program screen
   outputs were truncated at the 60 character boundary (to avoid wrapping
   them into something incomprehensible). In some cases portions of the
   program outputs were left out and replaced with ``...'' to reduce the
   overall length of the lesson document.
 
 
BRIEF
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``brief'', a utility program for summarizing contents
   of SPK files, to summarize the SPK files:
 
      dif_preenc174_nav_v1.bsp
      di_finalenc_nav_v3.bsp
 
   Detailed information about the ``brief'' interface is provided in the
   program's User's Guide (brief.ug) and the usage message displayed by the
   program.
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``brief'' to see usage (help) display.
 
       2.   Run ``brief'' to generate the basic summary of the SPK file
            ``di_finalenc_nav_v3.bsp''.
 
       3.   Run ``brief'' to generate a summary of
            ``di_finalenc_nav_v3.bsp'' in tabular format.
 
       4.   Run ``brief'' to generate a tabular summary of
            ``di_finalenc_nav_v3.bsp'' including centers of motion.
 
       5.   Run ``brief'' to generate a tabular summary for the
            ``combined'' ephemeris data provided by both SPK files,
            ``di_finalenc_nav_v3.bsp'' and ``dif_preenc174_nav_v1.bsp''.
 
 
Explanations
--------------------------------------------------------
 
       1.   Typing ``brief'' by itself displays a page long usage
            information explaining the command line syntax and all
            available command line options:
 
               % brief
               Brief.  Version: 2.3.1        (SPICE Toolkit N0061)
 
               Usage:
 
                  brief [-option] file [file ...]
 
               ...
 
            or with the ``-h'' option (even when files names and/or other
            options are also present):
 
               % brief -h
               ...
 
       2.   To generate the basic summary for a single SPK file ``brief'
            needs to be supplied with only one item on the command line --
            the name of the SPK file of interest:
 
               % brief di_finalenc_nav_v3.bsp
               Brief.  Version: 2.3.1        (SPICE Toolkit N0061)
 
 
               Summary for: di_finalenc_nav_v3.bsp
 
               Body: DEEP IMPACT IMPACTOR SPACECRAFT (-70)
                     Start of Interval (ET)              End of Interval (E
                     --------------------------------    ------------------
                     2005 JUL 03 06:16:04.184            2005 JUL 04 05:46:
 
               Body: DEEP IMPACT FLYBY SPACECRAFT (-140)
                     Start of Interval (ET)              End of Interval (E
                     --------------------------------    ------------------
                     2005 JUL 03 06:16:04.184            2005 JUL 05 05:45:
 
               Body: TEMPEL 1 (1000093)
                     Start of Interval (ET)              End of Interval (E
                     --------------------------------    ------------------
                     2005 JUL 03 06:16:04.184            2005 JUL 05 05:46:
 
 
            As seen in the output this SPK contains data for both DI
            spacecraft and the mission's primary target, comet TEMPEL 1,
            for the period starting shortly after the separation and ending
            about an hour after the impact.
 
            It is important to point out that in this report, as in all
            other summary reports generated by ``brief'', the coverage
            boundaries are shown as Ephemeris Time rather than UTC.
 
            Also note that since the coverages of the three bodies differ
            slightly the output contains three separate tables with the
            name and ID of each body provided in the table header. While
            this basic format works well in some cases, the tabular format
            discussed in the next step is easier to read.
 
       3.   To generate summary in the tabular format the ``-t'' option
            must be provided on the command line:
 
               % brief di_finalenc_nav_v3.bsp -t
               Brief.  Version: 2.3.1        (SPICE Toolkit N0061)
 
 
               Summary for: di_finalenc_nav_v3.bsp
 
               Bodies                               Start of Interval (ET)
               -------                              -----------------------
               -70 DEEP IMPACT IMPACTOR SPACECRAFT  2005 JUL 03 06:16:04.18
               -140 DEEP IMPACT FLYBY SPACECRAFT    2005 JUL 03 06:16:04.18
               1000093 TEMPEL 1                     2005 JUL 03 06:16:04.18
 
            Unlike in the basic report all of the bodies are now listed in
            one table with their names/IDs given in the left column.
 
            Note that the location of the ``-t'' option on the command line
            is not significant. It and any other command line option can be
            specified before, after, or even in between the SPK file
            name(s).
 
       4.   To generate a tabular summary including centers of motion for
            each of the bodies the ``-c'' option must be provided on the
            command line (``-t'' must be provided as well because the
            summary requested on this step should be in the tabular
            format):
 
               % brief di_finalenc_nav_v3.bsp -t -c
               Brief.  Version: 2.3.1        (SPICE Toolkit N0061)
 
 
               Summary for: di_finalenc_nav_v3.bsp
 
               Bodies
               -------
               -70 DEEP IMPACT IMPACTOR SPACECRAFT w.r.t. 1000093 TEMPEL 1
               -140 DEEP IMPACT FLYBY SPACECRAFT w.r.t. 1000093 TEMPEL 1
               1000093 TEMPEL 1 w.r.t. 10 SUN
 
            Note that now ``body - center of motion'' pairs appear in the
            left column of the table. If an SPK contains segments in which
            data for the same body are provided with respect to different
            centers, the table will contain a separate line for each pair.
            More than one line for a pair will be included if the coverage
            for that pair contains gaps.
 
            Generating a summary that shows centers of motion is important
            in many cases. One such case is when an SPK contains data only
            for the spacecraft. Determining the center(s) of motion of the
            spacecraft data is the first step in finding and loading
            additional SPKs that provide data for this(these) centers
            relative to the Solar System Barycenter so that an application
            could compute the spacecraft states corrected for light time
            and stellar aberration.
 
       5.   To generate a tabular summary for the ``combined'' ephemeris
            data provided by two or more SPK files the ``-a'' option must
            be provided on the command line in addition to the names of
            these files (``-t'' must also be provided because the summary
            requested in this step should be in the tabular format):
 
               % brief di_finalenc_nav_v3.bsp dif_preenc174_nav_v1.bsp -t
               -a
 
               Brief.  Version: 2.3.1        (SPICE Toolkit N0061)
 
               Summary for all files.
 
               Bodies                               Start of Interval (ET)
               -------                              -----------------------
               -70 DEEP IMPACT IMPACTOR SPACECRAFT  2005 JUL 03 06:16:04.18
               -140 DEEP IMPACT FLYBY SPACECRAFT    2005 JAN 12 19:23:32.06
               1 MERCURY BARYCENTER                 2005 JAN 12 19:23:32.06
               2 VENUS BARYCENTER                               Same covera
               ...
               499 MARS                                         Same covera
               1000004 BOETHIN                      2005 MAY 09 00:00:00.00
               1000093 TEMPEL 1                     2005 JAN 12 19:23:32.06
 
            Note that the summary indicates that it is for ``all files''
            and that the coverages for all bodies from both files are
            listed in one table. Also, note that the merge of the coverages
            for the same body provided by all SPKs given to ``brief'' is
            included in a single record for that body.
 
            This type of report is very useful when one needs to find out
            the totality of the SPK data that would be available to an
            application when it loads a given set of SPK files, especially
            if the set includes tens or even hundreds of files.
 
 
CKBRIEF
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``ckbrief'', a utility program for summarizing contents
   of CK files, to summarize the CK files:
 
      dii_sc_050112_050703.bc
      dii_sc_050703_050704.bc
 
   Use these FK, LSK, and SCLK files when needed to complete the task
   steps:
 
      di_v17.tf
      naif0008.tls
      dii_sclkscet_00008_science.tsc
 
   Detailed information about the ``ckbrief'' interface is provided in the
   program's User's Guide (ckbrief.ug) and the usage message displayed by
   the program.
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``ckbrief'' to see usage (help) display.
 
       2.   Run ``ckbrief'' to generate the basic summary for the
            ``dii_sc_050703_050704.bc'' CK file without use of additional
            kernels.
 
       3.   Run ``ckbrief'' to generate the basic summary for
            ``dii_sc_050703_050704.bc'' with times displayed as Ephemeris
            Times (ETs).
 
       4.   Run ``ckbrief'' to generate the basic summary for
            ``dii_sc_050703_050704.bc'' with times displayed as UTCs.
 
       5.   Run ``ckbrief'' to generate the basic summary for
            ``dii_sc_050703_050704.bc'' with times displayed as SCLKs.
 
       6.   Run ``ckbrief'' to generate a tabular summary for
            ``dii_sc_050703_050704.bc'' with times displayed as UTCs.
 
       7.   Run ``ckbrief'' to generate an interpolation interval summary
            for ``dii_sc_050703_050704.bc'' with times displayed as UTCs.
 
       8.   Run ``ckbrief'' to generate the basic summary for
            ``dii_sc_050703_050704.bc'' and ``dii_sc_050112_050703.bc''
            with times displayed as UTCs.
 
       9.   Run ``ckbrief'' to generate the basic summary for
            ``dii_sc_050703_050704.bc'' and ``dii_sc_050112_050703.bc''
            with times displayed as UTCs and the names or IDs of the
            frames, relative to which the orientation is given, included in
            the report.
 
 
Explanations
--------------------------------------------------------
 
       1.   Typing ``ckbrief'' by itself displays a page long usage
            information (help) explaining the command line syntax and all
            available command line options:
 
               % ckbrief
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
                    CKBRIEF is a command line program that allows you to ea
                    the pointing (orientation) data coverage of one or more
                    files. ``Coverage'' is used in the sense of specifying
                    for which orientation data are available.
 
               ...
 
            or with the ``-h'' option:
 
               % ckbrief -h
               ...
 
       2.   When ``ckbrief'' is provided with only the name(s) of the CK
            files it generates the basic summary that does not include
            coverage times:
 
               % ckbrief dii_sc_050703_050704.bc
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin ET        Interval End ET          AV
                 ------------------------ ------------------------ ---
                 NEED LSK AND SCLK FILES  NEED LSK AND SCLK FILES  Y
 
 
            Instead, the ``NEED LSK AND SCLK FILES'' phrase is displayed in
            the begin and end time columns reminding the user that the
            encoded SCLK time tags stored internally in the CK files cannot
            be converted to any other time system without LSK and SCLK
            data. The program can display the coverage as encoded SCLKs if
            the ``-dpsclk'' option is given:
 
               % ckbrief dii_sc_050703_050704.bc -dpsclk
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin TICKS     Interval End TICKS       AV
                 ------------------------ ------------------------ ---
                    44452501808.             44474333491.          Y
 
 
            but these encoded SCLK times are, in general, of very little
            use because they cannot be easily related to any other, more
            meaningful time systems.
 
       3.   To generate the basic summary with times displayed as ETs the
            names of an LSK file and an SCLK file containing data for the
            clock with which the data in the CK is tagged must be provided
            on ``ckbrief''s command line in addition to the name of the CK
            file to be summarized:
 
               % ckbrief dii_sc_050703_050704.bc naif0008.tls dii_sclkscet_
               00008_science.tsc
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin ET        Interval End ET          AV
                 ------------------------ ------------------------ ---
                 2005-JUL-03 06:04:07.362 2005-JUL-04 05:45:28.172 Y
 
 
            Note that the times are displayed as ETs, as indicated by the
            table column headers, to make the ``ckbrief'' basic output
            similar to that of the ``brief'' program. The last column in
            the table indicates whether the CK data for this ID include
            angular rates. If this CK contained data for two different
            structures, the output would have included two separate tables,
            one for each of the structures.
 
       4.   To generate the basic summary with times displayed as UTCs the
            ``-utc'' option must be specified on ``ckbrief''s command line
            in addition to the names of the CK, LSK, and SCLK files:
 
               % ckbrief dii_sc_050703_050704.bc naif0008.tls dii_sclkscet_
               00008_science.tsc -utc
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV
                 ------------------------ ------------------------ ---
                 2005-JUL-03 06:03:03.177 2005-JUL-04 05:44:23.988 Y
 
 
            The column headings is this report indicate that the times are
            UTCs.
 
            Note that the location of the ``-utc'' option on the command
            line is not significant. It and any other command line options
            can be specified before, after, or even in between the file
            name(s).
 
       5.   To generate the basic summary with times displayed as SCLKs the
            ``-sclk'' option must be specified on ``ckbrief''s command line
            in addition to the names of the CK, LSK, and SCLK files:
 
               % ckbrief dii_sc_050703_050704.bc naif0008.tls dii_sclkscet_
               00008_science.tsc -sclk
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin SCLK      Interval End SCLK        AV
                 ------------------------ ------------------------ ---
                 1/0173642585.048         1/0173727865.051         Y
 
 
            The column headings is this report indicate that the times are
            SCLKs.
 
       6.   To generate the tabular summary with times displayed as UTCs
            the ``-t'' option must be specified on ``ckbrief''s command
            line in addition to the names of the CK, LSK, and SCLK files
            and the ``-utc'' option:
 
               % ckbrief dii_sc_050703_050704.bc naif0008.tls dii_sclkscet_
               00008_science.tsc -utc -t
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Objects  Interval Begin UTC       Interval End UTC         A
               -------- ------------------------ ------------------------ -
               -70000   2005-JUL-03 06:03:03.177 2005-JUL-04 05:44:23.988 Y
 
 
            In the tabular summary the ID of the structure is shown in the
            left column of the table rather than in the table header.
 
            While for this particular CK file containing data for only one
            structure the tabular summary is not necessarily better than
            the basic summary, the tabular format is more desirable for CK
            files that contain data for many structures because it makes
            ``ckbrief''s report more compact and easier to read.
 
       7.   To generate the interpolation interval summary report with
            times displayed as UTCs the ``-dump'' option must be specified
            on ``ckbrief''s command line in addition to the names of the
            CK, LSK, and SCLK files and the ``-utc'' option:
 
               % ckbrief dii_sc_050703_050704.bc naif0008.tls dii_sclkscet_
               00008_science.tsc -utc -dump
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Segment No.: 1
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV
                 ------------------------ ------------------------ ---
                 2005-JUL-03 06:03:03.177 2005-JUL-03 06:55:51.207 Y
                 2005-JUL-03 06:57:03.208 2005-JUL-03 07:55:51.241 Y
                 ...
                 2005-JUL-04 03:51:59.913 2005-JUL-04 04:39:27.940 Y
                 2005-JUL-04 04:40:31.941 2005-JUL-04 05:44:23.988 Y
 
 
            This type of report is crucial in determining whether a CK file
            really provides data for a time of interest. Any other, non
            ``-dump'' report generated by ``ckbrief'' uses only the
            coverage information from the CK segment descriptors and does
            not provide visibility of the gaps that may exist in the
            coverages given in those descriptors.
 
            Note that this type of report contains a separate table for
            each of the CK file segments, with the segment number in the
            file shown before the table header.
 
       8.   To generate the basic summary report with UTC times for more
            than one CK file the names of all CK files to be summarized
            should be specified on ``ckbrief''s command line along with the
            names of the LSK and SCLK files and the ``-utc'' option:
 
               % ckbrief dii_sc_050112_050703.bc dii_sc_050703_050704.bc na
               if0008.tls dii_sclkscet_00008_science.tsc -utc
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050112_050703.bc
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV
                 ------------------------ ------------------------ ---
                 2005-JAN-12 19:25:45.675 2005-JUL-03 05:59:58.281 Y
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV
                 ------------------------ ------------------------ ---
                 2005-JUL-03 06:03:03.177 2005-JUL-04 05:44:23.988 Y
 
 
            Note that the summary for each of the CK files is given in a
            separate table.
 
       9.   To generate the basic summary report with UTC times, including
            the names or IDs of the frames relative to which the
            orientation is given, the ``-rel'' option must be specified on
            ``ckbrief''s command line in addition to the names of the CK,
            LSK and SCLK files and the ``-utc'' option:
 
               % ckbrief dii_sc_050112_050703.bc dii_sc_050703_050704.bc na
               if0008.tls dii_sclkscet_00008_science.tsc -utc -rel
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050112_050703.bc
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV  Rela
                 ------------------------ ------------------------ --- ----
                 2005-JAN-12 19:25:45.675 2005-JUL-03 05:59:58.281 Y   -140
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV  Rela
                 ------------------------ ------------------------ --- ----
                 2005-JUL-03 06:03:03.177 2005-JUL-04 05:44:23.988 Y   J200
 
 
            Note that the tables in this report include an additional
            column, ``Relative to FRAME,'' providing either the name or the
            ID of the reference frame relative to which the orientation for
            a particular structure is given in the CK segments. ``ckbrief''
            displays the frame ID when it cannot map it to the frame name,
            for example when a frame is not one of the frames built into
            the Toolkit. If an FK file defining this frame is available, it
            can be added to the ``ckbrief'' command line to make
            ``ckbrief'' load the FK and map the frame ID to the frame name
            using the loaded frame definition:
 
               % ckbrief dii_sc_050112_050703.bc dii_sc_050703_050704.bc na
               if0008.tls dii_sclkscet_00008_science.tsc di_v17.tf -utc
               -rel
 
               CKBRIEF Version: 3.2.0, 2006-11-02. SPICE Toolkit Version: N
 
 
               Summary for: dii_sc_050112_050703.bc
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV  Rela
                 ------------------------ ------------------------ --- ----
                 2005-JAN-12 19:25:45.675 2005-JUL-03 05:59:58.281 Y   DIF_
 
 
               Summary for: dii_sc_050703_050704.bc
 
               Object:  -70000
                 Interval Begin UTC       Interval End UTC         AV  Rela
                 ------------------------ ------------------------ --- ----
                 2005-JUL-03 06:03:03.177 2005-JUL-04 05:44:23.988 Y   J200
 
 
 
SPACIT
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``spacit'', an interactive utility program for
   converting, summarizing contents of, and viewing internal comments in
   SPICE binary kernels, to summarize these SPK and CK files:
 
      dif_preenc174_nav_v1.bsp
      dii_sc_050703_050704.bc
 
   Use these LSK and SCLK files when needed to complete the task steps:
 
      naif0008.tls
      dii_sclkscet_00008_science.tsc
 
   Detailed information about the ``spacit'' interface is provided in the
   program's User's Guide (spacit.ug).
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``spacit'' to generate a summary for the entire SPK file
            ``dif_preenc174_nav_v1.bsp''.
 
       2.   Run ``spacit'' to generate a summary for the entire CK file
            ``dii_sc_050703_050704.bc''.
 
 
Explanations
--------------------------------------------------------
 
       1.   To generate a summary for an entire SPK file the ``Summarize
            binary file'' option from the ``SPACIT Options'' menu should be
            picked by entering the letter ``s'' in response to the
            ``Option:'' prompt. Then the names of the SPK and LSK files
            should be entered in response to the the ``Binary file:'' and
            ``Leapseconds file:'' prompts. Finally the ``Summarize entire
            file'' option from the ``SPK Summary Options'' menu should be
            picked by entering the letter ``f'' in response to the
            ``Option:'' prompt:
 
               % spacit
 
 
 
                   Welcome to SPACIT Version: 7.1.1
                         (Spice Toolkit N0061)
 
 
 
                        SPACIT Options
 
                  ( Q ) Quit.
                  ( L ) Log SPACIT output to a file.
                  ( T ) Convert transfer file to binary file.
                  ( B ) Convert binary file to transfer file.
                  ( S ) Summarize binary file.
                  ( R ) Read comment area of binary file.
 
                  Option: s
 
                  Binary file     : dif_preenc174_nav_v1.bsp
                  Leapseconds file: naif0008.tls
 
                  Loading the Leapseconds kernel file. Please wait ...
 
 
                        SPK Summary Options
 
                  ( Q ) Quit, returning to main menu.
 
                  ( F ) Summarize entire file.
                  ( B ) Summarize by NAIF body ID code.
                  ( T ) Summarize by time interval.
 
                  Option: f
 
               ************************************************************
 
               Summary for SPK file: dif_preenc174_nav_v1.bsp
               Leapseconds File    : naif0008.tls
               Summary Type        : Entire File
 
               ------------------------------------------------------------
                  Segment ID     : pfile_od004-radio.nio
                  Target Body    : Body -140, DEEP IMPACT FLYBY SPACECRAFT
                  Center Body    : Body 10, SUN
                  Reference frame: Frame 1, J2000
                  SPK Data Type  : Type 1
                     Description : Modified Difference Array
                  UTC Start Time : 2005 JAN 15 16:47:07.324
                  UTC Stop Time  : 2005 JAN 22 04:00:00.000
                  ET Start Time  : 2005 JAN 15 16:48:11.507
                  ET Stop time   : 2005 JAN 22 04:01:04.184
               ------------------------------------------------------------
 
               ...
 
               ------------------------------------------------------------
                  Segment ID     : DE-0405LE-0405
                  Target Body    : Body 1, MERCURY BARYCENTER
                  Center Body    : Body 0, SOLAR SYSTEM BARYCENTER
                  Reference frame: Frame 1, J2000
                  SPK Data Type  : Type 2
                     Description : Fixed Width, Fixed Order Chebyshev Polyn
                  UTC Start Time : 2005 JAN 12 19:22:27.884
                  UTC Stop Time  : 2009 JAN 15 00:03:54.816
                  ET Start Time  : 2005 JAN 12 19:23:32.068
                  ET Stop time   : 2009 JAN 15 00:05:00.000
               ------------------------------------------------------------
 
               ************************************************************
 
               ...
 
            To quit ``spacit'' after displaying the summary the letter
            ``q'' should be entered twice in response to the ``Option:''
            prompt.
 
            Note that ``spacit'', unlike ``brief'', does not provide much
            flexibility in formating the SPK summary output. On the other
            hand its simple segment-by-segment report contains all segment
            descriptor details for each of the segments. The segment
            reports include the body, center, segment ID string, reference
            frame name and ID, SPK data type and its description, and the
            coverage boundaries shown as ETs and UTCs.
 
            Knowing this ``extra'' information, more than provided by
            ``brief'', may be essential in some cases. For example, the
            segment ID string may identify the planetary ephemeris version
            or the producer of the data (note ``DE-0405LE-0405'' in the
            blocks for the planetary ephemerides segments). Knowing the
            reference frame may be important to determine if additional
            kernels providing orientation for this frame have to be loaded
            together with the SPK in order for the SPK to be used.
 
       2.   To generate a summary for an entire CK file the ``Summarize
            binary file'' option from the ``SPACIT Options'' menu should be
            picked by entering the letter ``s'' in response to the
            ``Option:'' prompt. Then the names of the CK, LSK, and SCLK
            files should be entered in response to the ``Binary file:'',
            ``Leapseconds file:'', and ``SCLK file:'' prompts. Finally the
            ``Summarize entire file'' option from the ``CK Summary
            Options'' menu should be picked by entering the letter ``f'' in
            response to the ``Option:'' prompt:
 
               % spacit
 
 
 
                   Welcome to SPACIT Version: 7.1.1
                         (Spice Toolkit N0061)
 
 
 
                        SPACIT Options
 
                  ( Q ) Quit.
                  ( L ) Log SPACIT output to a file.
                  ( T ) Convert transfer file to binary file.
                  ( B ) Convert binary file to transfer file.
                  ( S ) Summarize binary file.
                  ( R ) Read comment area of binary file.
 
                  Option: s
 
                  Binary file     : dii_sc_050703_050704.bc
                  Leapseconds file: naif0008.tls
                  SCLK file       : dii_sclkscet_00008_science.tsc
 
                  Loading the Leapseconds kernel file. Please wait ...
                  Loading the SCLK kernel file. Please wait ...
 
 
                        CK Summary Options
 
                  ( Q ) Quit, returning to main menu.
 
                  ( F ) Summarize entire file.
                  ( I ) Summarize by NAIF instrument ID code.
                  ( U ) Summarize by UTC time interval.
                  ( S ) Summarize by SCLK time interval.
 
                  Option: f
 
               ************************************************************
 
               Summary for CK file: dii_sc_050703_050704.bc
               Leapseconds File   : naif0008.tls
               SCLK File          : dii_sclkscet_00008_science
               Summary Type       : Entire File
 
               ------------------------------------------------------------
                  Segment ID     : DII TELEMETRED ATTITUDE AND RATE
                  Instrument Code: -70000
                  Spacecraft     : Body -70, DEEP IMPACT IMPACTOR SPACECRAF
                  Reference Frame: Frame 1, J2000
                  CK Data Type   : Type 3
                     Description : Continuous Pointing: Linear Interpolatio
                  Available Data : Pointing and Angular Velocity
                  UTC Start Time : 2005 JUL 03 06:03:03.178
                  UTC Stop Time  : 2005 JUL 04 05:44:23.989
                  SCLK Start Time: 1/0173642585.048
                  SCLK Stop Time : 1/0173727865.051
               ------------------------------------------------------------
 
               ************************************************************
 
               ...
 
            To quit ``spacit'' after displaying the summary ``q'' should be
            entered twice in response to the ``Option:'' prompt.
 
            Note that ``spacit'', unlike ``ckbrief'', does not provide much
            flexibility in formating the CK summary output. On the other
            hand its simple segment-by-segment report contains all segment
            descriptor details for each of the segments. The segment
            reports include the CK ID, reference frame, coverage, segment
            ID string, name and ID of the spacecraft to which this CK ID is
            related, and the CK data type and its description.
 
            Knowing this ``extra'' information, more than provided by
            ``ckbrief'', may be essential in some cases. For example, the
            segment ID string may contain a concise description of the data
            (note ``DII TELEMETRED ATTITUDE AND RATE'' for the only segment
            in this CK file). Knowing the CK data type may suggest the best
            approach to access the data. For example, Type 1 CK files
            containing discrete orientation and rarely produced these days
            should be accessed using the middle level CK readers
            CKGP/CKGPAV with a non-zero tolerance because the higher level
            interface PXFORM/SXFORM will not be able to read them using
            zero tolerance.
 
 
COMMNT
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``commnt'', a utility program for accessing and
   manipulating internal comments in SPICE binary kernels, to view and
   extract comments from this SPK file:
 
      dif_preenc174_nav_v1.bsp
 
   Detailed information about the ``commnt'' interface is provided in the
   program's User's Guide (commnt.ug).
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``commnt'' in command-line mode to view internal comments
            included in the ``dif_preenc174_nav_v1.bsp'' SPK file.
 
       2.   Run ``commnt'' in command-line mode to extract to a text file
            the internal comments included in the
            ``dif_preenc174_nav_v1.bsp'' SPK file.
 
       3.   Run ``commnt'' in interactive mode to view internal comments
            included in the ``dif_preenc174_nav_v1.bsp'' SPK file.
 
 
Explanations
--------------------------------------------------------
 
       1.   To view comments included in a binary SPICE kernel by running
            ``commnt'' in command-line mode the ``-r'' option followed by
            the kernel name must be provided on ``commnt''s command line:
 
               % commnt -r dif_preenc174_nav_v1.bsp
 
               \beginlabel
               PDS_VERSION_ID               = PDS3
               RECORD_TYPE                  = FIXED_LENGTH
 
               ...
 
               NOTE                         = "See comments in the file for
               OBJECT                       = SPICE_KERNEL
                 INTERCHANGE_FORMAT         = BINARY
                 KERNEL_TYPE                = EPHEMERIS
                 DESCRIPTION                = "DIF SPICE SP-Kernel file con
               spacecraft trajectory reconstructed from radio tracking data
               planetary ephemerides and ephemerides for the DI mission tar
               DI Navigation Team, JPL, covering the whole mission. "
               END_OBJECT                   = SPICE_KERNEL
               \endlabel
 
 
               DIF SPK file, Complete Mission, Last Pre-Encounter Solution
               ============================================================
 
                    Created by Boris Semenov, NAIF/JPL, September 20, 2005
                    files produced by the Deep Impact (DI) Navigation (NAV)
                    during mission operations.
 
 
               Objects in the Ephemeris
               --------------------------------------------------------
 
                    This file contains ephemeris data for Deep Impact Flyby
                    spacecraft (NAIF ID -140), DI primary mission target co
                    1 (NAIF ID 1000093), DI extended mission opportunity ta
                    Boethin (NAIF ID 1000004), Sun, and planets and planet
                    barycenters.
 
 
               ...
 
                    The spacecraft trajectory segment boundary discontinuit
                    this file are:
 
                    #
                    # Summary of discontinuities at segment boundaries for
                    # SPK file dif_preenc174_nav_v1.bsp:
                    #
                    #  BOUNDARY TIME (UTC)   DOWNTRK INPLANE  NORMAL
                    #----------------------- ------- ------- -------
                    2005-01-22T04:00:00.000  -0.030   0.106   0.102
                    2005-02-12T00:00:00.000  -0.118   0.113   0.519
                    2005-05-06T00:00:00.000  -0.069  -0.025   0.274
                    2005-06-01T00:00:00.000   0.139   0.066  -0.380
                    2005-07-07T00:00:00.000  51.862  43.397  40.628
 
 
            Ideally all SPICE kernels should contain extensive internal
            comments describing data origin, data producer, coverage, etc.
            This is usually more true for the files that are a part of a
            mission's SPICE archive than for the kernels generated during
            operations but even ``ops'' kernels sometimes include very
            lengthy multi-page comments. Since ``commnt'' prints all of the
            comments to the screen at once, users may find it desirable to
            pipe ``commnt''s output through ``more'' or a similar utility
            to be able to read the displayed text starting from the top:
 
               % commnt -r dif_preenc174_nav_v1.bsp | more
 
               \beginlabel
               PDS_VERSION_ID               = PDS3
               RECORD_TYPE                  = FIXED_LENGTH
               RECORD_BYTES                 = 1024
               ^SPICE_KERNEL                = "dif_preenc174_nav_v1.bsp"
               MISSION_NAME                 = "DEEP IMPACT"
               SPACECRAFT_NAME              = "DEEP IMPACT FLYBY SPACECRAFT
               DATA_SET_ID                  = "DI-C-SPICE-6-V1.0"
               KERNEL_TYPE_ID               = SPK
               PRODUCT_ID                   = "dif_preenc174_nav_v1.bsp"
               PRODUCT_CREATION_TIME        = 2006-03-01T14:13:15
               PRODUCER_ID                  = "DI NAV/JPL"
               MISSION_PHASE_NAME           = {
                                              "9P CRUISE",
                                              "9P ENCOUNTER",
                                              "9P POST-ENCOUNTER CRUISE"
                                              }
               PRODUCT_VERSION_TYPE         = ACTUAL
               PLATFORM_OR_MOUNTING_NAME    = "N/A"
               START_TIME                   = 2005-01-12T19:22:28
               STOP_TIME                    = 2009-01-15T00:03:55
               --More--
 
            Another possibility is to extract comments into a text file and
            then examine the file using a text editor or a file contents
            viewing utility run from a terminal or command window.
 
       2.   To extract comments included in a binary SPICE kernel by
            running ``commnt'' in command-line mode the ``-e'' option
            followed by two file names -- the kernel file name and the name
            of a text file into which the comments are to be written --
            must be provided on ``commnt''s command line:
 
               % commnt -e dif_preenc174_nav_v1.bsp comments.txt
 
               % more comments.txt
               \beginlabel
               PDS_VERSION_ID               = PDS3
               RECORD_TYPE                  = FIXED_LENGTH
               RECORD_BYTES                 = 1024
               ^SPICE_KERNEL                = "dif_preenc174_nav_v1.bsp"
               MISSION_NAME                 = "DEEP IMPACT"
               SPACECRAFT_NAME              = "DEEP IMPACT FLYBY SPACECRAFT
               DATA_SET_ID                  = "DI-C-SPICE-6-V1.0"
               KERNEL_TYPE_ID               = SPK
               PRODUCT_ID                   = "dif_preenc174_nav_v1.bsp"
               PRODUCT_CREATION_TIME        = 2006-03-01T14:13:15
               PRODUCER_ID                  = "DI NAV/JPL"
               MISSION_PHASE_NAME           = {
                                              "9P CRUISE",
                                              "9P ENCOUNTER",
                                              "9P POST-ENCOUNTER CRUISE"
                                              }
               PRODUCT_VERSION_TYPE         = ACTUAL
               PLATFORM_OR_MOUNTING_NAME    = "N/A"
               START_TIME                   = 2005-01-12T19:22:28
               STOP_TIME                    = 2009-01-15T00:03:55
               --More--
 
            If a text file with the specified name already exists
            ``commnt'' will not overwrite it and will stop with an error
            message instead.
 
       3.   To view comments included in a binary SPICE kernel by running
            ``commnt'' in interactive mode, invoke ``commnt'' without any
            command line arguments, pick the ``Read the comments in a
            binary file'' option from the ``COMMNT Options'' menu by
            entering the ``r'' letter in response to the ``Option:''
            prompt, then enter the kernel file name in response to the
            ``Filename?'' prompt:
 
               % commnt
 
                  Welcome to COMMNT Version: 6.0.1
                       (Spice Toolkit N0061)
 
                        COMMNT Options
 
                  ( Q ) Quit.
                  ( A ) Add comments to a binary file.
                  ( R ) Read the comments in a binary file.
                  ( E ) Extract comments from a binary file.
                  ( D ) Delete the comments in a binary file.
 
                  Option: r
 
               Enter the name of the binary file.
 
               Filename? dif_preenc174_nav_v1.bsp
 
               Reading the comment area of the SPK file.
 
               File: dif_preenc174_nav_v1.bsp
 
               \beginlabel
               PDS_VERSION_ID               = PDS3
               RECORD_TYPE                  = FIXED_LENGTH
 
               ...
 
                    The spacecraft trajectory segment boundary discontinuit
                    this file are:
 
                    #
                    # Summary of discontinuities at segment boundaries for
                    # SPK file dif_preenc174_nav_v1.bsp:
                    #
                    #  BOUNDARY TIME (UTC)   DOWNTRK INPLANE  NORMAL
                    #----------------------- ------- ------- -------
                    2005-01-22T04:00:00.000  -0.030   0.106   0.102
                    2005-02-12T00:00:00.000  -0.118   0.113   0.519
                    2005-05-06T00:00:00.000  -0.069  -0.025   0.274
                    2005-06-01T00:00:00.000   0.139   0.066  -0.380
                    2005-07-07T00:00:00.000  51.862  43.397  40.628
 
 
               The comments were successfully read.
                        COMMNT Options
 
                  ( Q ) Quit.
                  ( A ) Add comments to a binary file.
                  ( R ) Read the comments in a binary file.
                  ( E ) Extract comments from a binary file.
                  ( D ) Delete the comments in a binary file.
 
                  Option:
 
 
            To quit ``commnt'' after displaying the summary ``q'' must be
            entered in response to the ``Option:'' prompt.
 
 
TOXFR
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``toxfr'', a command line utility program for
   converting SPICE binary kernels to transfer format, to convert this SPK
   file:
 
      dif_preenc174_nav_v1.bsp
 
   Detailed information about the ``toxfr'' interface is provided in the
   program's User's Guide (toxfr.ug).
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``toxfr'' to see usage (help) display.
 
       2.   Run ``toxfr'' to convert the SPK file
            ``dif_preenc174_nav_v1.bsp'' to transfer format without
            explicitly specifying the output transfer file name.
 
       3.   Run ``toxfr'' to convert the SPK file
            ``dif_preenc174_nav_v1.bsp'' to transfer format with explicitly
            specifying the output transfer file name.
 
 
Explanations
--------------------------------------------------------
 
       1.   Typing ``toxfr'' by itself displays a short usage message
            explaining the command line syntax:
 
              % toxfr
 
              ============================================================
 
              Toolkit version: N0061
 
              SPICE(USAGEERROR)
 
              Usage: toxfr file.b* [file.x*]
 
              A traceback follows.  The name of the highest level module i
              TOXFR
 
              ============================================================
 
       2.   If the command line provided to ``toxfr'' contains only the
            name of the binary kernel to be converted, the program writes
            output to a file with the same name as the input file and with
            an extension specific to the transfer kernels for that kernel
            type:
 
               % toxfr dif_preenc174_nav_v1.bsp
               Converting: dif_preenc174_nav_v1.bsp
                       To: dif_preenc174_nav_v1.xsp
 
            Note that the output file has extension ``.xsp'' because the
            program recognized the ``.bsp'' extension, standard for binary
            SPKs, and replaced it with the ``.xsp'' extension, standard for
            transfer format SPKs. If the program cannot recognize the
            extension of the input file, it gives the output file the
            ``.xfr'' extension.
 
            If a file with the name that ``toxfr'' picked for the output
            file already exists the program will not overwrite it and will
            stop with an error message instead.
 
       3.   For ``toxfr'' to create a transfer file with a name different
            from the automatically picked ``default'' name, the output file
            name must be specified explicitly on the command line after the
            name of the binary kernel to be converted:
 
               % toxfr dif_preenc174_nav_v1.bsp my.xsp
               Converting: dif_preenc174_nav_v1.bsp
                       To: my.xsp
 
            Assigning the output file name explicitly is usually needed
            when the output file should be placed into a different
            directory, when a transfer file with the name that would be
            generated by ``toxfr'' by default already exists and should be
            preserved, or when the input binary file has a non-standard
            extension.
 
 
TOBIN
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``tobin'', a command line utility program for
   converting SPICE kernels in transfer format to binary format, to convert
   the transfer format SPK file generated as part of the previous task
   (``TOXFR'' task):
 
      my.xsp
 
   Detailed information about the ``tobin'' interface is provided in the
   program's User's Guide (tobin.ug).
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``tobin'' to see usage (help) display.
 
       2.   Run ``tobin'' to convert the transfer SPK file ``my.xsp'' to
            binary format without explicitly specifying the output binary
            SPK file name.
 
       3.   Run ``tobin'' to convert the transfer SPK file ``my.xsp'' to
            binary format with explicitly specifying the output binary SPK
            file name.
 
 
Explanations
--------------------------------------------------------
 
       1.   Typing ``tobin'' by itself displays a short usage message
            explaining the command line syntax:
 
               % tobin
 
               ============================================================
 
               Toolkit version: N0061
 
               SPICE(USAGEERROR)
 
               Usage: tobin file.x* [file.b*]
 
               A traceback follows.  The name of the highest level module i
               TOBIN
 
               ============================================================
 
       2.   If the command line provided to ``tobin'' contains only the
            name of the transfer kernel to be converted, the program writes
            output to a file with the same name as the input file and with
            an extension specific to the binary kernels for that kernel
            type:
 
               % tobin my.xsp
               Converting: my.xsp
                       To: my.bsp
 
            Note that the output file has extension ``.bsp'' because the
            program recognized the ``.xsp'' extension, standard for
            transfer SPKs, and replaced it with the ``.bsp'' extension,
            standard for binary SPKs. If the program cannot recognize the
            extension of the input file, it gives the output file the
            ``.bin'' extension.
 
            If a file with the name that ``tobin'' picked for the output
            file already exists the program will not overwrite it and will
            stop with an error message instead.
 
       3.   For ``tobin'' to create a binary file with a name different
            from the automatically picked ``default'' name, the output file
            name must be specified explicitly on the command line after the
            name of the transfer kernel to be converted:
 
               % tobin my.xsp di_spk.bsp
               Converting: my.xsp
                       To: di_spk.bsp
 
            Assigning the output file name explicitly is usually needed
            when the output file should be placed into a different
            directory, when a binary kernel with the name that would be
            generated by ``tobin'' by default already exists and should be
            preserved, or when the input transfer file has a non-standard
            extension.
 
 
CHRONOS
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``chronos'', a command line utility program for
   converting between various time systems and time formats, to perform a
   number of time conversions using these supporting kernels:
 
      naif0008.tls
      dii_sclkscet_00008_science.tsc
 
   Detailed information about the ``chronos'' interface is provided in the
   program's User's Guide (chronos.ug).
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``chronos'' to see usage (help) display.
 
       2.   Run ``chronos'' to convert UTC time ``2005 JUL 05 04:00:00'' to
            Ephemeris Time (ET) in calendar format.
 
       3.   Run ``chronos'' to convert UTC time ``2005 JUL 05 04:00:00'' to
            ET seconds past J2000.
 
       4.   Run ``chronos'' to convert UTC time ``2005 JUL 05 04:00:00'' to
            Deep Impact Impactor spacecraft SCLK time.
 
 
Explanations
--------------------------------------------------------
 
       1.   Typing ``chronos'' by itself displays a half-page of usage
            (help) information explaining the command line syntax and all
            available command line options:
 
               % chronos
 
               CHRONOS -- Universal Time Conversion Tool
               Version 2.1.0, August 18, 2006
 
               CHRONOS Usage
               ------------------------------------------------------------
 
                  To convert time from one supported system/type to another
 
                     % CHRONOS -SETUP <setup file name OR kernel file name(
                               -FROM <"from" time system>
                              [-FROMTYPE <"from" time type>]
                               -TO <"to" time system>
                              [-TOTYPE <"to" time type>]
                              [-FORMAT <output time format picture>]
                               -TIME <input time> | -BATCH
                              [-SC <sc ID>]
                              [-CENTER <cental body ID>]
                              [-LANDINGTIME <UTC time of the landing>]
                              [-SOL1INDEX <index of the first SOL>]
                              [-NOLABEL]
                              [-TRACE]
 
                  To display usage:               % CHRONOS [-HELP|-H]
                  To display help:                % CHRONOS -USAGE|-U
                  To display setup file template: % CHRONOS -TEMPLATE
 
                  The case of command line switches is insignificant. Switc
                  square braces [] are optional. See User's Guide for detai
 
 
            or with the ``-u'' or ``-usage'' option (even when files names
            and/or other options are also present):
 
               % chronos -u
               ...
 
       2.   To convert a UTC time to ET in calendar format ``chronos'' must
            be provided with the following information on the command line:
            the name of an LSK file specified using the ``-setup'' option,
            the ``utc'' tag identifying the input time system as UTC
            specified using the ``-from'' option, the ``et'' tag
            identifying the output time system as ET specified using the
            ``-to'' option, and the UTC time to be converted specified
            using the ``-time'' option:
 
               % chronos -setup naif0008.tls -from utc -to et -time 2005
               JUL 05 04:00:00
 
               2005-07-05, 04:01:04.184                          (ET/SCET)
 
            In this run both the input time and the output time are assumed
            to be for the same instant and point in space, thus letting the
            ``-fromtype'' and ``-totype'' options default to SCET is
            appropriate. None of the other optional arguments are needed
            for this conversion because some of them are not applicable
            (for example ``-sc'' or ``-landingtime'') while the others are
            OK with their built in, default values.
 
            If this conversion had to be done for a large number of input
            UTC times, the most efficient way to do it would be to list
            these times, one per line, in a text file, replace ``-time 2005
            JUL 05 04:00:00'' on the command line with ``-batch'' and pipe
            the contents of the text file into ``chronos'' via standard
            input. Then ``chronos'' would process the command line and load
            kernels only once and would print to standard output the
            converted time for each of the input times, one per line:
 
               % cat time.txt
               2005 JUL 05 04:00:00
               2005 JUL 05 05:00:00
               2005 JUL 05 06:00:00
 
               % chronos -setup naif0008.tls -from utc -to et -batch < tim
               e.txt
 
               2005-07-05, 04:01:04.184                          (ET/SCET)
               2005-07-05, 05:01:04.184                          (ET/SCET)
               2005-07-05, 06:01:04.184                          (ET/SCET)
 
            The ``-nolabel'' option can be added to the command line to
            eliminate the trailing label accompanying each of the output
            times (``(ET/SCET)'' in the example above).
 
       3.   To convert a UTC time to ET seconds past J2000 ``chronos'' must
            be provided with the following information on the command line:
            the name of an LSK file specified using the ``-setup'' option,
            the ``utc'' tag identifying the input time system as UTC
            specified using the ``-from'' option, the ``et'' tag
            identifying the output time system as ET specified using the
            ``-to'' option, the ``seconds'' tag identifying the output time
            type as seconds past J2000 specified using the ``-totype''
            option, and the UTC time to be converted specified using the
            ``-time'' option:
 
               % chronos -setup naif0008.tls -from utc -to et -totype seco
               nds -time 2005 JUL 05 04:00:00
 
               173808064.184                                  (ET/SECONDS)
 
       4.   To convert a UTC time to SCLK ``chronos'' must be provided with
            the following information on the command line: the names of an
            LSK file and an SCLK file specified using the ``-setup''
            option, the spacecraft ID specified using the ``-sc'' option,
            the ``utc'' tag specified using the ``-from'' option, the
            ``sclk'' tag identifying the output time system as SCLK
            specified using the ``-to'' option, and the UTC time to be
            converted specified using the ``-time'' option:
 
               % chronos -setup naif0008.tls dii_sclkscet_00008_science.t
               sc -sc -70 -from utc -to sclk -time 2005 JUL 05 04:00:00
 
               1/0173808000.118                               (SCLK/SCLK)
 
            Note that both an LSK file and an SCLK file must be provided
            using the ``setup'' option because data from both files are
            needed for this conversion.
 
 
STATES
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``states'', an interactive cookbook program that
   demonstrates how to use Toolkit routines to obtain state vectors, to
   compute a state using these SPK and LSK files:
 
      di_finalenc_nav_v3.bsp
      naif0008.tls
 
   Although the ``states'' program is not intended to be used as executable
   -- the primary purpose of including it in the toolkit is to provide a
   simple source code example of using high level toolkit functions that
   compute state vectors -- as all other Toolkit applications it comes with
   a User's Guide (states.ug) describing its interface.
 
 
Steps
--------------------------------------------------------
 
       1.   run ``states'' to compute the geometric state of the comet
            TEMPEL 1 relative to the Sun at 2005 JUL 05 04:00:00 in the
            ECLIPJ2000 reference frame.
 
 
Explanations
--------------------------------------------------------
 
       1.   After starting ``states'', follow the prompts and enter the
            name of the LSK file, the name of the SPK file, the name of the
            observing body, the name of the target body, the number of
            states to be calculated, the time, the name of the reference
            frame, and the desired aberration correction:
 
               % states
 
                               Welcome to STATES
 
               This program demonstrates the use of NAIF S- and P-
               Kernel (SPK) files and subroutines by computing the
               state of a target body as seen from an observing
               body at a number of epochs within a given time
               interval.
 
 
               Enter the name of a leapseconds kernel file: naif0008.tls
 
               Enter the name of a binary SPK ephemeris file: di_finalenc_n
               av_v3.bsp
 
               Enter the name of the observing body: sun
 
               Enter the name of a target body: tempel 1
 
               Enter the number of states to be calculated: 1
 
               Enter the UTC time: 2005 JUL 05 04:00:00
 
               Enter the inertial reference frame (eg:J2000): ECLIPJ2000
 
               Type of correction                              Type of stat
               ------------------------------------------------------------
               'LT+S'    Light-time and stellar aberration    Apparent stat
               'LT'      Light-time only                      True state
               'NONE'    No correction                        Geometric sta
 
               Enter LT+S, LT, or NONE: NONE
 
               Working ... Please wait
 
               For time 1 of 1, the state of:
               Body            : tempel 1
               Relative to body: sun
               In Frame        : ECLIPJ2000
               At UTC time     : 2005 JUL 05 04:00:00
 
                                Position (km)              Velocity (km/s)
                           -----------------------     --------------------
                         X: -0.8549549029932106E+08      0.2719316117375332
                         Y: -0.2084670053553146E+09     -0.1115748888018338
                         Z:  0.9044625066075269E+06     -0.5462400774687403
                 MAGNITUDE:  0.2253193050667428E+09      0.2989641107150566
 
 
            Note that ``states'' prompts only two file -- LSK and SPK. If
            additional kernels are required to compute a state of interest
            the easiest way to provide these kernels to ``states'' is to
            prepare a meta-kernel listing LSK and these kernels and enter
            the name of this meta-kernel in response to the LSK prompt
            instead of the LSK name.
 
 
SPKDIFF
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``spkdiff'', a command line utility program for
   comparing trajectories stored in two SPK files, to compare these SPK
   kernels:
 
      dif_preenc174_nav_v1.bsp
      di_finalenc_nav_v3.bsp
 
   Detailed information about the ``spkdiff'' interface is provided in the
   program's User's Guide (spkdiff.ug).
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``spkdiff'' to see usage (help) display.
 
       2.   Run ``spkdiff'' to generate the ``Basic Report'' on differences
            of the Deep Impact Flyby (DIF) trajectories relative to the
            comet Tempel 1 provided by ``dif_preenc174_nav_v1.bsp'' and
            ``di_finalenc_nav_v3.bsp''.
 
       3.   Run ``spkdiff'' to generate the ``View Frame Statistics
            Report'' on differences of the DIF trajectories relative to
            Tempel 1 provided by ``dif_preenc174_nav_v1.bsp'' and
            ``di_finalenc_nav_v3.bsp''.
 
       4.   Run ``spkdiff'' to generate the ``Difference Dump Report'' on
            differences of the DIF trajectories relative to Tempel 1
            provided by ``dif_preenc174_nav_v1.bsp'' and
            ``di_finalenc_nav_v3.bsp''.
 
       5.   Run ``spkdiff'' to generate the ``View Frame Difference Dump
            Report'' on differences of the DIF trajectories relative to
            Tempel 1 provided by ``dif_preenc174_nav_v1.bsp'' and
            ``di_finalenc_nav_v3.bsp''.
 
       6.   Run ``spkdiff'' to generate the ``View Frame Difference Dump
            Report'' with time tags in ISO DOY format
            (YYYY-DOYTHR:MN:SC.###) on differences of the DIF trajectories
            relative to Tempel 1 provided by ``dif_preenc174_nav_v1.bsp''
            and ``di_finalenc_nav_v3.bsp''.
 
       7.   Run ``spkdiff'' to generate the ``View Frame Difference Dump
            Report'' with time tags in ISO DOY format
            (YYYY-DOYTHR:MN:SC.###) on differences of the DIF trajectories
            relative to Tempel 1 provided by ``dif_preenc174_nav_v1.bsp''
            and ``di_finalenc_nav_v3.bsp'' during the interval from
            ``2005-186T03:00'' to ``2005-186T05:00''.
 
       8.   Run ``spkdiff'' to generate the ``View Frame Difference Dump
            Report'' with time tags in ISO DOY format
            (YYYY-DOYTHR:MN:SC.###) on differences of the DIF trajectories
            relative to Tempel 1 provided by ``dif_preenc174_nav_v1.bsp''
            and ``di_finalenc_nav_v3.bsp'' during the interval from
            ``2005-186T03:00'' to ``2005-186T05:00'' with states sampled
            every ten minutes.
 
 
Explanations
--------------------------------------------------------
 
       1.   Typing ``spkdiff'' by itself displays a half-page of usage
            (help) information explaining the command line syntax and all
            available command line options:
 
               % spkdiff
 
               spkdiff -- Version 1.0.0, July 20, 2006 -- Toolkit Version N
 
                  spkdiff computes differences between geometric states obt
                  two SPK files and either displays these differences or sh
                  about them (see the User's Guide for more details.) The p
 
                     % spkdiff [options] <first SPK file> <second SPK file>
 
                  Options are shown below. Order and case of keys are not s
                  Values must be space-separated from keys, i.e. '-n 10', n
 
                     -b1 <first body name or ID>
                     -c1 <first center name or ID>
                     -r1 <first reference frame name>
                     -b2 <second body name or ID>
                     -c2 <second center name or ID>
                     -r2 <second reference frame name>
                     -k  <other kernel file name(s)>
                     -b  <interval start time>
                     -e  <interval stop time>
                     -s  <time step in seconds>
                     -n  <number of states: 2 to 1000000 (default: 1000)>
                     -f  <output time format (default: TDB seconds past J20
                     -t  <report type: basic|stats|dump|dumpvf (default: ba
 
 
       2.   To generate the ``Basic Report'' on differences between two SPK
            files it is sufficient in most cases to provide ``spkdiff''
            only with the names of the SPK files:
 
               % spkdiff dif_preenc174_nav_v1.bsp di_finalenc_nav_v3.bsp
 
               #
               # Comparison of 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'S
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # with 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'S
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # evenly-spaced with 171.14114108565 second (0d 0h 2m 51.141
               # within the time interval
               #
               #    from '2005 JUL 03 06:16:04.184 TDB' (173643364.18405 TD
               #    to   '2005 JUL 05 05:45:34.183 TDB' (173814334.18399 TD
               #
 
               Relative differences in state vectors:
 
                                             maximum                 averag
 
                 Position:             5.7433875616092E-07      2.658197967
                 Velocity:             3.5311760378989E-03      7.037404294
 
 
               Absolute differences in state vectors:
 
                                             maximum                 averag
 
                 Position (km):        1.2918999431552E+02      5.989230358
                 Velocity (km/s):      7.9483307482710E-02      1.581288819
 
 
            Note that the order in which SPK names are provided on the
            command line affects the choice of the body-center-frame
            combination, for which the states used in comparison will be
            calculated because the program picks this combination by
            examining the first SPK file. In cases when the program picks a
            body-center-frame combination for which the second SPK file
            does not contain data, it will display an error message rather
            than doing a comparison. This would be the case if the
            ``di_finalenc_nav_v3.bsp'' SPK file was listed first of the two
            SPKs used in this step. ``spkdiff'' would attempt to make a
            comparison for the Deep Impact Impactor (DII) spacecraft (the
            segment for DII is the first segment in
            ``di_finalenc_nav_v3.bsp'', thus DII will be picked as the
            body) for which the other SPK does not contain data:
 
               % spkdiff di_finalenc_nav_v3.bsp dif_preenc174_nav_v1.bsp
 
               ============================================================
 
               Toolkit version: N0061
 
               SPICE(3NODATAFORBODY)
 
               SPK file 'dif_preenc174_nav_v1.bsp' does not contain data fo
               body 'DEEP IMPACT IMPACTOR SPACECRAFT'(-70) specified on the
 
               A traceback follows.  The name of the highest level module i
               spkdiff --> CHWCML
 
               ============================================================
 
            In such cases -- and, in general, in any case when the SPKs
            that are being compared provide data for more than one body --
            it is better to explicitly specify the name or the ID of the
            body for which comparison is sought using either the ``-b1''
            option or the ``-b2'' option:
 
               % spkdiff -b1 -140 di_finalenc_nav_v3.bsp dif_preenc174_nav_
               v1.bsp
 
               #
               # Comparison of 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # with 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # evenly-spaced with 171.14114108565 second (0d 0h 2m 51.141
               # within the time interval
               #
               #    from '2005 JUL 03 06:16:04.184 TDB' (173643364.18405 TD
               #    to   '2005 JUL 05 05:45:34.183 TDB' (173814334.18399 TD
               #
 
               Relative differences in state vectors:
 
                                             maximum                 averag
 
                 Position:             2.2265666444092E-01      1.341183451
                 Velocity:             7.7342629071411E-03      1.550818952
 
 
               Absolute differences in state vectors:
 
                                             maximum                 averag
 
                 Position (km):        2.0310929065151E+02      1.568497359
                 Velocity (km/s):      7.9470466093664E-02      1.582125015
 
 
            Note that the basic reports generated by the
 
               % spkdiff dif_preenc174_nav_v1.bsp di_finalenc_nav_v3.bsp
 
               ...
 
            and the
 
               % spkdiff -b1 -140 di_finalenc_nav_v3.bsp dif_preenc174_nav_
               v1.bsp
 
               ...
 
            commands are different. The first of the two reports is for DIF
            trajectories relative to the Sun (DIF-Sun is the body-center
            pair picked from ``dif_preenc174_nav_v1.bsp'') while the second
            is for DIF trajectories relative to the comet Tempel 1
            (DIF-Tempel 1 is the body-center pair picked from
            ``di_finalenc_nav_v3.bsp''). Similar to that for bodies,
            ``spkdiff'' has options -- ``-c1'' and ``-c2'' -- that can be
            used to specify the centers for trajectories sampled from each
            of the two SPKs explicitly.
 
       3.   To generate the ``View Frame Statistics Report'' on differences
            between two SPK files ``spkdiff'' must be provided with the
            ``stats'' tag using the ``-t'' option, followed by the options
            (if any are needed) picking the right body-center-frame
            combination for each of the two SPK files, followed by the
            names of the files:
 
               % spkdiff -t stats -b1 -140 -c1 1000093 di_finalenc_nav_v3.b
               sp dif_preenc174_nav_v1.bsp
 
               #
               # Comparison of 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # with 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # evenly-spaced with 171.14114108565 second (0d 0h 2m 51.141
               # within the time interval
               #
               #    from '2005 JUL 03 06:16:04.184 TDB' (173643364.18405 TD
               #    to   '2005 JUL 05 05:45:34.183 TDB' (173814334.18399 TD
               #
 
               1) Average components of position difference vectors in view
                  frame coordinates:
 
                  1a) Down track (km):                        141.304792673
 
                  1b) In orbit plane (km):                    2.19944880951
 
                  1c) Normal to orbit plane (km):            -2.54558248303
 
                  1d) Average delta time down track (sec):    13.8592441085
 
               ...
 
                  5e) Epoch (TDB, seconds past J2000):        173643364.184
 
                  5f) Epoch (TDB, calendar format):           2005-JUL-03-0
 
 
            Note that to facilitate filtering and parsing of this report
            using utilities like ``grep'' each of the items in the report
            occupies a separate line that starts with a unique
            ``identifier'' (``1a)'', ``1b)'', etc.) and ends with the item
            value.
 
       4.   To generate the ``Difference Dump Report'' on differences
            between two SPK files ``spkdiff'' must be provided with the
            ``dump'' tag using the ``-t'' option, followed by the options
            (if any are needed) picking the right body-center-frame
            combination for each of the two SPK files, followed by the
            names of the files:
 
               % spkdiff -t dump -b1 -140 -c1 1000093 di_finalenc_nav_v3.bs
               p dif_preenc174_nav_v1.bsp
 
               #
               # Comparison of 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # with 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # evenly-spaced with 171.14114108565 second (0d 0h 2m 51.141
               # within the time interval
               #
               #    from '2005 JUL 03 06:16:04.184 TDB' (173643364.18405 TD
               #    to   '2005 JUL 05 05:45:34.183 TDB' (173814334.18399 TD
               #
               # time, (x1-x2), (y1-y2), (z1-z2), (vx1-vx2), (vy1-vy2), (vz
               1.7364336418405E+08 -1.8375003233796E+02 -7.1250147502171E+0
               1.7364353532519E+08 -1.7444854285719E+02 -6.7077228545619E+0
               1.7364370646633E+08 -1.6884788472275E+02 -6.4548013248423E+0
               1.7364387760747E+08 -1.6697802157979E+02 -6.3678136817645E+0
               1.7364404874861E+08 -1.6689960146637E+02 -6.3603913064115E+0
               ...
               1.7381416304285E+08 -7.0171493083122E+01 -3.9950623055687E+0
               1.7381433418399E+08 -7.0069659960689E+01 -3.9935477027262E+0
 
            Since both ``dump'' reports print all difference lines to the
            screen at once, users may find it desirable to pipe
            ``spkdiff''s output through ``more'' or a similar utility to be
            able to read the displayed text starting from the top.
 
       5.   To generate the ``View Frame Difference Dump Report'' on
            differences between two SPK files ``spkdiff'' must be provided
            with the ``dumpvf'' tag using the ``-t'' option, followed by
            the options (if any are needed) picking the right
            body-center-frame combination for each of the two SPK files,
            followed by the names of the files:
 
               % spkdiff -t dumpvf -b1 -140 -c1 1000093 di_finalenc_nav_v3.
               bsp dif_preenc174_nav_v1.bsp
 
               #
               # Comparison of 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # with 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # evenly-spaced with 171.14114108565 second (0d 0h 2m 51.141
               # within the time interval
               #
               #    from '2005 JUL 03 06:16:04.184 TDB' (173643364.18405 TD
               #    to   '2005 JUL 05 05:45:34.183 TDB' (173814334.18399 TD
               #
               # time, down_track_p_diff, normal_to_plane_p_diff, in_plane_
               1.7364336418405E+08 +1.5782062666755E+02 -8.6614056142247E+0
               1.7364353532519E+08 +1.4649666193458E+02 -8.6381063884318E+0
               1.7364370646633E+08 +1.3972679080400E+02 -8.6148850160950E+0
               ...
               1.7381416304285E+08 +1.4144474095255E+02 +7.4490533513132E+0
               1.7381433418399E+08 +1.4144339442723E+02 +7.4664581930583E+0
 
       6.   To generate the ``View Frame Difference Dump Report'' on
            differences between two SPK files with times given in ISO DOY
            format ``spkdiff'' must be provided with the ``dumpvf'' tag
            using the ``-t'' option, the picture describing the ISO DOY
            time format (per TIMOUT requirement) using the ``-f'' option, a
            LSK file name using ``-k'' option, the options (if any are
            needed) picking the right body-center-frame combination for
            each of the two SPK files, followed by the names of the files:
 
               % spkdiff -t dumpvf -f 'YYYY-DOYTHR:MN:SC.###' -k naif0008.t
               ls -b1 -140 -c1 1000093 di_finalenc_nav_v3.bsp dif_preenc174
               _nav_v1.bsp
 
               #
               # Comparison of 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # with 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # evenly-spaced with 171.14114108565 second (0d 0h 2m 51.141
               # within the time interval
               #
               #    from '2005 JUL 03 06:16:04.184 TDB' (173643364.18405 TD
               #    to   '2005 JUL 05 05:45:34.183 TDB' (173814334.18399 TD
               #
               # using additional data from these kernels
               #
               #    'naif0008.tls'
               #
               # time, down_track_p_diff, normal_to_plane_p_diff, in_plane_
               2005-184T06:15:00.000 +1.5782062666755E+02 -8.6614056142247E
               2005-184T06:17:51.141 +1.4649666193458E+02 -8.6381063884318E
               2005-184T06:20:42.282 +1.3972679080400E+02 -8.6148850160950E
               ...
               2005-186T05:41:38.858 +1.4144474095255E+02 +7.4490533513132E
               2005-186T05:44:30.000 +1.4144339442723E+02 +7.4664581930583E
 
            Providing an LSK file is required when the ``-f'' option is
            specified because the program uses SPICE's TIMOUT routine to
            format times for output and this routine needs LSK data. If no
            LSK is given on the command line when time formatting is
            requested ``spkdiff'' will stop with the following error:
 
               % spkdiff -t dumpvf -f 'YYYY-DOYTHR:MN:SC.###' -b1 -140 -c1
               1000093 di_finalenc_nav_v3.bsp dif_preenc174_nav_v1.bsp
 
               #
               ...
               ============================================================
 
               Toolkit version: N0061
 
               SPICE(MISSINGTIMEINFO)
 
               The following, needed to convert between the input uniform t
               not found in the kernel pool: DELTET/DELTA_T_A, DELTET/K, DE
               Your program may have failed to load a leapseconds kernel. O
               causes of this problem include loading an invalid leapsecond
               lacks an initial \begindata marker or final newline characte
               corrupted---or deleting previously loaded kernel pool variab
               UNLOAD, KCLEAR, or CLPOOL. Use the SPICE routine FURNSH (in
               FURNSH is an entry point of KEEPER) to load a leapseconds ke
               kernel is up to date. See the Kernel and Time Required Readi
               Kernels" and "LSK and SCLK" SPICE Tutorials for details.
 
               A traceback follows.  The name of the highest level module i
               spkdiff --> STDIFF --> TIMOUT --> UNITIM
 
               ============================================================
 
       7.   To generate a report on differences between two SPK files for a
            specified interval of time ``spkdiff'' must be provided with
            the begin and end times of this interval using the ``-b'' and
            ``-e'' options in addition to any other options followed by the
            names of the files:
 
               % spkdiff -t dumpvf -f 'YYYY-DOYTHR:MN:SC.###' -k naif0008.t
               ls -b 2005-186T03:00 -e 2005-186T05:00 -b1 -140 -c1 1000093
               di_finalenc_nav_v3.bsp dif_preenc174_nav_v1.bsp
 
               #
               # Comparison of 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # with 1000 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # evenly-spaced with 7.2072072048803 second (0d 0h 0m 7.2072
               # within the time interval
               #
               #    from '2005 JUL 05 03:01:04.183 TDB' (173804464.18399 TD
               #    to   '2005 JUL 05 05:01:04.183 TDB' (173811664.18399 TD
               #
               # using additional data from these kernels
               #
               #    'naif0008.tls'
               #
               # time, down_track_p_diff, normal_to_plane_p_diff, in_plane_
               2005-186T03:00:00.000 +1.4154921446446E+02 +6.4448848992533E
               2005-186T03:00:07.207 +1.4154907859830E+02 +6.4455384786604E
               2005-186T03:00:14.414 +1.4154892614482E+02 +6.4461575858493E
               ...
               2005-186T04:59:52.792 +1.4147346706276E+02 +7.1817591286974E
               2005-186T05:00:00.000 +1.4147347203042E+02 +7.1825243077425E
 
       8.   To generate a report on differences between two SPK files using
            states sampled at a specified time step ``spkdiff'' must be
            provided with the time step in seconds using the ``-s'' option
            in addition to any other options followed by the names of the
            files:
 
               % spkdiff -t dumpvf -f 'YYYY-DOYTHR:MN:SC.###' -k naif0008.t
               ls -b 2005-186T03:00 -e 2005-186T05:00 -s 600 -b 1 -140 -c1
               1000093 di_finalenc_nav_v3.bsp dif_preenc174_nav_v1.bsp
 
               #
               # Comparison of 13 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'di_finalenc_nav_v3.bsp'
               #
               # with 13 'J2000'-referenced geometric states
               #
               #    of 'DEEP IMPACT FLYBY SPACECRAFT' (-140) relative to 'T
               #    from SPK 'dif_preenc174_nav_v1.bsp'
               #
               # evenly-spaced with 600.00000000000 second (0d 0h 10m 0.000
               # within the time interval
               #
               #    from '2005 JUL 05 03:01:04.183 TDB' (173804464.18399 TD
               #    to   '2005 JUL 05 05:01:04.183 TDB' (173811664.18399 TD
               #
               # using additional data from these kernels
               #
               #    'naif0008.tls'
               #
               # time, down_track_p_diff, normal_to_plane_p_diff, in_plane_
               2005-186T03:00:00.000 +1.4154921446446E+02 +6.4448848992533E
               2005-186T03:10:00.000 +1.4154314730387E+02 +6.5040755037385E
               2005-186T03:20:00.000 +1.4153731846733E+02 +6.5643598474778E
               2005-186T03:30:00.000 +1.4153124096038E+02 +6.6256300011018E
               2005-186T03:40:00.000 +1.4152459254164E+02 +6.6862766878730E
               2005-186T03:50:00.000 +1.4151855690873E+02 +6.7469944286093E
               2005-186T04:00:00.000 +1.4151230121125E+02 +6.8089315976010E
               2005-186T04:10:00.000 +1.4150583588593E+02 +6.8699758002280E
               2005-186T04:20:00.000 +1.4149967515646E+02 +6.9332270052340E
               2005-186T04:30:00.000 +1.4149333543142E+02 +6.9947127932754E
               2005-186T04:40:00.000 +1.4148606471834E+02 +7.0575019380439E
               2005-186T04:50:00.000 +1.4148022258664E+02 +7.1203995033684E
               2005-186T05:00:00.000 +1.4147347203042E+02 +7.1825243077425E
 
 
FRMDIFF
===========================================================================
 
 
Task Statement
--------------------------------------------------------
 
   Practice running ``frmdiff'', a command line utility program for
   comparing or sampling frame orientations. In this exercise you will
   compare or sample orientations of CASSINI frames defined in and/or
   supported by these kernels:
 
      08110_08152pl_live.bc
      08132_08137ra.bc
      cas_v40.tf
      cas00137.tsc
      naif0008.tls
 
   Detailed information about the ``frmdiff'' interface is provided in the
   program's User's Guide (frmdiff.ug).
 
 
Steps
--------------------------------------------------------
 
       1.   Run ``frmdiff'' to see usage (help) display.
 
       2.   Run ``frmdiff'' to generate the ``Basic Report'' on differences
            of the CASSINI spacecraft orientations relative to the J2000
            inertial frame provided by ``08132_08137ra.bc'' and
            ``08110_08152pl_live.bc''.
 
       3.   Run ``frmdiff'' to generate the ``Statistics Report'' on
            differences of the CASSINI spacecraft orientations relative to
            the J2000 inertial frame provided by ``08132_08137ra.bc'' and
            ``08110_08152pl_live.bc'' using a 5 second step size.
 
       4.   Run ``frmdiff'' to generate the ``Angle and Axis Difference
            Dump Report'' on differences of the CASSINI spacecraft
            orientations relative to the J2000 inertial frame provided by
            ``08132_08137ra.bc'' and ``08110_08152pl_live.bc'' using a 10
            second step size.
 
       5.   Run ``frmdiff'' to generate the ``SPICE-Style Quaternion Dump
            Report'' sampling the CASSINI spacecraft orientation and
            angular velocity relative to the J2000 inertial frame provided
            by ``08132_08137ra.bc'', tagged with SCLK times with a 10
            second step size.
 
       6.   Run ``frmdiff'' to generate the ``Euler Angle Dump Report''
            sampling the CASSINI spacecraft orientation relative to the
            J2000 inertial frame provided by ``08132_08137ra.bc''. The
            report should contain Euler angles in degrees for a ``Z-Y-Z''
            rotation sequence tagged with UTC in ISO DOY format
            (YYYY-DOYTHR:MN:SC.###) with a 1 second step size during the
            interval from ``2008-MAY-12 10:00'' to ``2008-MAY-12 12:00''
            UTC.
 
       7.   Run ``frmdiff'' to generate the ``Coverage Intervals Dump
            Report'' for ``08132_08137ra.bc'' with time tags shown as UTC
            in ISO DATE format (YYYY-MM-DDTHR:MN:SC.###).
 
       8.   Run ``frmdiff'' to generate the ``Coverage Gaps Dump Report''
            for ``08132_08137ra.bc'' with time tags shown as UTC in ISO
            DATE format (YYYY-MM-DDTHR:MN:SC.###).
 
       9.   Run ``frmdiff'' to display misalignment between the
            ``CASSINI_ISS_NAC'' and ``CASSINI_ISS_WAC'' frames as Euler
            angles in degrees for an ``X-Y-Z'' rotation sequence.
 
 
Explanations
--------------------------------------------------------
 
       1.   Typing ``frmdiff'' by itself displays a half-page of usage
            (help) information explaining the command line syntax and all
            available command line options:
 
               % frmdiff
 
               frmdiff -- Version 1.0.0, February 10, 2009 -- Toolkit Versi
 
                  frmdiff provides a simple way of sampling orientation of
                  comparing orientations of two frames known to SPICE and s
                  data from SPICE kernels. The program usage is:
 
                     % frmdiff [options] <first kernel name> <second kernel
                     % frmdiff [options] <kernel name>
                     % frmdiff [options]
 
                  where kernel can be a CK, an FK, or a PCK. Options are sh
                  Order and case of keys are not significant. Values must b
                  space-separated from keys, i.e. '-n 10', not '-n10'.
 
                     -k  <supporting kernel(s) name(s)>
                     -f1 <first ``from'' frame, name or ID>
                     -t1 <first ``to'' frame, name or ID>
                     -c1 <first frame for coverage look up, name or ID>
                     -k1 <additional supporting kernel(s) for first file>
                     -f2 <second ``from'' frame, name or ID>
                     -t2 <second ``to'' frame, name or ID>
                     -c2 <second frame for coverage look up, name or ID>
                     -k2 <additional supporting kernel(s) for second file>
                     -a  <compare angular velocities: yes|no>
                     -m  <frame for angular velocities: from|to>
                     -b  <interval start time>
                     -e  <interval stop time>
                     -n  <number of points: 1 to 1000000 (default: 1000)>
                     -s  <time step in seconds>
                     -f  <time format: et|sclk|sclkd|ticks|picture_for_TIMO
                     -t  <report: basic|stats|dumpaa|dumpm|dumpqs|dumpqo|du
                     -o  <rotation axes order (default: z y x)>
                     -x  <units for output angles> (only for -t dumpaa and
 
 
       2.   To generate the ``Basic Report'' on differences between two CK
            files it is sufficient in most cases to provide ``frmdiff''
            only with the names of the supporting LSK, SCLK, and FK files
            using the ``-k'' option and the names of the two CK files:
 
               % frmdiff -k naif0008.tls cas00137.tsc cas_v40.tf 08132_0813
               7ra.bc 08110_08152pl_live.bc
 
               #
               # Comparison of 994 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08132_08137ra.bc
               #
               # with 994 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08110_08152pl_live.bc
               #
               # with a 261.76763488717 second (0:00:04:21.767635) step siz
               # within the non-continuous (with 5 gaps) time period
               #
               #    from '2008 MAY 11 00:01:06.765' TDB (263736066.76544 TD
               #    to   '2008 MAY 14 00:01:05.184' TDB (263995265.18467 TD
               #
 
               Absolute difference magnitudes:
 
                                                    maximum
 
                 Rotation (rad):             +2.1382305885650E-02      +5.9
 
 
            Note that the two CKs to be compared have to be provided as the
            last two items on the command line while all supporting kernels
            must be provided before them. Also note that in this case the
            program automatically picked the frames and the time interval
            for comparison by examining the data in the first of the two
            CKs (``08132_08137ra.bc'') and included these names and time
            boundaries as well as the other automatically picked items --
            the time step and the number of steps -- in the report header.
 
       3.   To generate the ``Statistics Report'' on differences between
            two CK files using a particular sampling step ``frmdiff'' must
            be provided with the names of supporting kernels specified
            using the ``-k'' option, the ``stats'' tag using the ``-t''
            option, and the step size using the ``-s'' option, followed by
            the names of two CKs to be compared:
 
               % frmdiff -k naif0008.tls cas00137.tsc cas_v40.tf -t stats
               -s 5 08132_08137ra.bc 08110_08152pl_live.bc
 
               #
               # Comparison of 51731 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08132_08137ra.bc
               #
               # with 51731 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08110_08152pl_live.bc
               #
               # with a 5.0000000000000 second (0:00:00:05.000000) step siz
               # within the non-continuous (with 5 gaps) time period
               #
               #    from '2008 MAY 11 00:01:06.765' TDB (263736066.76544 TD
               #    to   '2008 MAY 14 00:01:05.184' TDB (263995265.18467 TD
               #
 
               1) Average difference
 
                  1a) Rotation (rad):                               0.00059
 
 
               2) RMS of difference
 
                  2a) Rotation (rad):                               0.00239
 
 
               3) Maximum rotation difference
 
                  3a) Rotation (rad):                               0.02205
 
                  3b) Epoch (TDB, seconds past J2000):              2638568
 
                  3c) Epoch (TDB, calendar format):                 2008-MA
 
 
            To facilitate filtering and parsing of this report using
            utilities like ``grep'' each of the items in the report
            occupies a separate line that starts with a unique
            ``identifier'' (``1a)'', ``3a)'', etc.) and ends with the item
            value.
 
       4.   To generate the ``Angle and Axis Difference Dump Report'' on
            differences between two CK files using a particular sampling
            step ``frmdiff'' must be provided with the names of supporting
            kernels specified using the ``-k'' option, the ``dumpaa'' tag
            using the ``-t'' option, and the step size using the ``-s''
            option, followed by the names of two CKs to be compared:
 
               % frmdiff -k naif0008.tls cas00137.tsc cas_v40.tf -t dumpaa
               -s 10 08132_08137ra.bc 08110_08152pl_live.bc
 
               #
               # Comparison of 25869 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08132_08137ra.bc
               #
               # with 25869 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08110_08152pl_live.bc
               #
               # with a 10.000000000000 second (0:00:00:10.000000) step siz
               # within the non-continuous (with 5 gaps) time period
               #
               #    from '2008 MAY 11 00:01:06.765' TDB (263736066.76544 TD
               #    to   '2008 MAY 14 00:01:05.184' TDB (263995265.18467 TD
               #
               # Times are TDB seconds past J2000.
               #
               # angle is shown in radians.
               #
               # time, angle, axis_x, axis_y, axis_z
               +2.6373606676544E+08 +7.0339739249521E-04 -7.0414946683369E-
               +2.6373607676544E+08 +7.1952179054201E-04 -3.1512009275414E-
               +2.6373608676544E+08 +7.7560586484534E-04 -1.6887101147269E-
               ...
               +2.6399524722951E+08 +2.4560146109228E-05 +1.5574999384954E-
               +2.6399525722951E+08 +4.6330796897041E-05 -1.1215437867925E-
               +2.6399526518467E+08 +4.3066921035168E-05 +2.1392352889108E-
 
            Since all ``dump'' reports print all difference or sample lines
            to the screen at once, users may find it desirable to pipe
            ``frmdiff''s output through ``more'' or a similar utility to be
            able to read the displayed text starting from the top, or to
            redirect the output to a file for subsequent plotting.
 
       5.   To generate the ``SPICE-Style Quaternion Dump Report'' with
            samples of orientation and angular velocity from a CK file
            using a particular sampling step ``frmdiff'' must be provided
            with the names of supporting kernels specified using the ``-k''
            option, the ``dumpqs'' tag using the ``-t'' option, the step
            size using the ``-s'' option, and the ``yes'' tag using the
            ``-a'' option, followed by the name of the CK from which
            orientation is to be sampled:
 
               % frmdiff -k naif0008.tls cas00137.tsc cas_v40.tf -t dumpqs
               -s 10 -a yes 08132_08137ra.bc
 
               #
               # Sampling of 25869 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08132_08137ra.bc
               #
               # with a 10.000000000000 second (0:00:00:10.000000) step siz
               # within the non-continuous (with 5 gaps) time period
               #
               #    from '2008 MAY 11 00:01:06.765' TDB (263736066.76544 TD
               #    to   '2008 MAY 14 00:01:05.184' TDB (263995265.18467 TD
               #
               # including angular velocities relative to 'from' frame.
               #
               # Times are TDB seconds past J2000.
               #
               # time, q_cos, q_sin1, q_sin2, q_sin3, av_x, av_y, av_z
               +2.6373606676544E+08 +4.2765566350171E-01 +6.1995251219409E-
               +2.6373607676544E+08 +4.1487117144731E-01 +6.2143765069334E-
               +2.6373608676544E+08 +4.0196021073660E-01 +6.2267117608015E-
               ...
               +2.6399524722951E+08 +4.6868056473485E-01 -1.2207597036621E-
               +2.6399525722951E+08 +4.6870380200417E-01 -1.2237579486654E-
               +2.6399526518467E+08 +4.6870380004563E-01 -1.2237920889302E-
 
            Note that the report header indicates that the program was run
            in the sampling mode and that the output table includes angular
            velocities relative to the ``from'' frame in addition to
            quaternions.
 
       6.   To generate the ``Euler Angle Dump Report'' with samples of
            orientation using a particular sampling step over a particular
            interval of time with angles in particular units for a
            particular rotation sequence and report time tags shown as UTCs
            in a particular format ``frmdiff'' must be provided with the
            names of supporting kernels specified using the ``-k'' option,
            the ``dumpea'' tag using the ``-t'' option, the step size using
            the ``-s'' option, the time boundaries using the ``-b'' and
            ``-e'' options, the angle rotation sequence using the ``-o''
            option, the angle units using the ``-x'' option and the output
            time format using the ``-f'' option (for ISO DOY the format
            string is 'YYYY-DOYTHR:MN:SC.### ::RND'), followed by the name
            of the CK from which orientation is to be sampled:
 
               % frmdiff -k naif0008.tls cas00137.tsc cas_v40.tf -t dumpea
               -s 1 -b 2008-MAY-12 10:00 -e 2008-MAY-12 12:00 -o z y z
               -x degrees -f 'YYYY-DOYTHR:MN:SC.### ::RND' 08132_08137ra.bc
 
               #
               # Sampling of 7201 rotations
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08132_08137ra.bc
               #
               # with a 1.0000000000000 second (0:00:00:01.000000) step siz
               # within the continuous time period
               #
               #    from '2008 MAY 12 10:01:05.185' TDB (263858465.18530 TD
               #    to   '2008 MAY 12 12:01:05.185' TDB (263865665.18530 TD
               #
               # Times were generated by TIMOUT using 'YYYY-DOYTHR:MN:SC.##
               #
               # angles are shown in degrees.
               #
               # time, ang3_about_Z, ang2_about_Y, ang1_about_Z
               2008-133T10:00:00.000 +4.3056059795798E+01 +6.6322394077835E
               2008-133T10:00:01.000 +4.3073142191077E+01 +6.6235882496104E
               2008-133T10:00:02.000 +4.3094082386298E+01 +6.6150227150557E
               ...
               2008-133T11:59:58.000 +1.6306650969729E+02 +6.4432822285149E
               2008-133T11:59:59.000 +1.6299991511258E+02 +6.4483185277512E
               2008-133T12:00:00.000 +1.6293345369662E+02 +6.4533661172721E
 
            This kind of report is very useful for sampling actual
            orientation provided in a CK file with respect to a dynamic
            frame representing an ideal orientation mode. For example,
            sampling actual CK-based orientation relative to a dynamic
            nadir-pointed frame with the +Z axis pointing nadir and the +X
            axis along the spacecraft velocity, with the output given as
            Euler angles for the Z-Y-X rotation sequence, would show
            angular offsets in yaw, pitch and roll angles.
 
       7.   To generate the ``Coverage Intervals Dump Report'' with
            interval boundaries shown as UTCs in a particular format for a
            CK file ``frmdiff'' must be provided with the names of
            supporting kernels specified using the ``-k'' option, the
            ``dumpc'' tag using the ``-t'' option, and the output time
            format using the ``-f'' option (for ISO DATE the format string
            is ``YYYY-MM-DDTHR:MN:SC.### ::RND''), followed by the name of
            the CK for which the coverage report is to be shown:
 
               % frmdiff -k naif0008.tls cas00137.tsc cas_v40.tf -t dumpc
               -f 'YYYY-MM-DDTHR:MN:SC.### ::RND' 08132_08137ra.bc
 
               #
               # Coverage for rotation
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08132_08137ra.bc
               #
               # with a 261.76763488717 second (0:00:04:21.767635) step siz
               # within the non-continuous (with 5 gaps) time period
               #
               #    from '2008 MAY 11 00:01:06.765' TDB (263736066.76544 TD
               #    to   '2008 MAY 14 00:01:05.184' TDB (263995265.18467 TD
               #
               # Times were generated by TIMOUT using 'YYYY-MM-DDTHR:MN:SC.
               #
               # interval_start, interval_stop, interval_duration_sec, inte
               2008-05-11T00:00:01.580 2008-05-11T05:44:57.684       20696.
               2008-05-11T05:45:25.684 2008-05-11T22:29:53.258       60267.
               2008-05-11T22:30:13.258 2008-05-12T05:20:25.084       24611.
               2008-05-12T05:27:01.081 2008-05-12T13:37:52.873       29451.
               2008-05-12T13:39:40.873 2008-05-13T22:13:52.044      117251.
               2008-05-13T22:14:12.044 2008-05-13T23:59:59.999        6347.
 
            Note that while this type of report is similar to the
            ``intervals'' report provided by ``ckrbrief,'' using the
            ``-dump'' option, ``frmdiff''s report is more flexible because
            it allows for a greater number of output time formats, more
            concise because it combines interval information that came from
            many segments into a single table, and more informative because
            it includes interval durations in addition to interval
            boundaries.
 
       8.   To generate the ``Coverage Gaps Dump Report'' with gap
            boundaries shown as UTCs in a particular format for a CK file
            ``frmdiff'' must be provided with the names of supporting
            kernels specified using the ``-k'' option, the ``dumpg'' tag
            using the ``-t'' option, and the output time format using the
            ``-f'' option (for ISO DATE the format string is
            ``YYYY-MM-DDTHR:MN:SC.### ::RND''), followed by the name of the
            CK for which the gap report is to be shown:
 
               % frmdiff -k naif0008.tls cas00137.tsc cas_v40.tf -t dumpg
               -f 'YYYY-MM-DDTHR:MN:SC.### ::RND' 08132_08137ra.bc
 
               #
               # Coverage for rotation
               #
               #    from 'J2000' (1) to 'CASSINI_SC_COORD' (-82000)
               #    computed using
               #
               #       naif0008.tls cas00137.tsc cas_v40.tf
               #       08132_08137ra.bc
               #
               # with a 261.76763488717 second (0:00:04:21.767635) step siz
               # within the non-continuous (with 5 gaps) time period
               #
               #    from '2008 MAY 11 00:01:06.765' TDB (263736066.76544 TD
               #    to   '2008 MAY 14 00:01:05.184' TDB (263995265.18467 TD
               #
               # Times were generated by TIMOUT using 'YYYY-MM-DDTHR:MN:SC.
               #
               # gap_start, gap_stop, gap_duration_sec, gap_duration_string
               2008-05-11T05:44:57.684 2008-05-11T05:45:25.684          27.
               2008-05-11T22:29:53.258 2008-05-11T22:30:13.258          19.
               2008-05-12T05:20:25.084 2008-05-12T05:27:01.081         395.
               2008-05-12T13:37:52.873 2008-05-12T13:39:40.873         107.
               2008-05-13T22:13:52.044 2008-05-13T22:14:12.044          19.
 
       9.   To display the misalignment between two instrument frames
            defined as fixed-offset frames with respect to the spacecraft
            frame -- as is the case for the ``CASSINI_ISS_NAC'' and
            ``CASSINI_ISS_WAC'' frames -- ``frmdiff'' must be provided with
            the names of the FK (defining the frames) and LSK (needed to
            convert time bounds given on the command line) using the ``-k''
            option, the names of the frames using the ``-f1'' and ``-t1''
            options, the ``dumpea'' tag telling the program to display
            Euler angles using the ``-t'' option, the time boundaries set
            to the same arbitrary UTC using the ``-b'' and ``-e'' options,
            the angle rotation sequence using the ``-o'' option, and the
            angle units using the ``-x'' option:
 
               % frmdiff -k naif0008.tls cas_v40.tf -f1 CASSINI_ISS_NAC
               -t1 CASSINI_ISS_WAC -t dumpea -b 2005-01-01 -e 2005-01-01
               -o x y z -x degrees
 
               #
               # Sampling of 1 rotations
               #
               #    from 'CASSINI_ISS_NAC' (-82360) to 'CASSINI_ISS_WAC' (-
               #    computed using
               #
               #       naif0008.tls cas_v40.tf
               #
               # at continuous coverage intervals' endpoints
               # within the continuous time period
               #
               #    from '2005 JAN 01 00:01:04.183' TDB (157809664.18393 TD
               #    to   '2005 JAN 01 00:01:04.183' TDB (157809664.18393 TD
               #
               # Times are TDB seconds past J2000.
               #
               # angles are shown in degrees.
               #
               # time, ang3_about_X, ang2_about_Y, ang1_about_Z
               +1.5780966418393E+08 -3.6817224296505E-02 -2.4358034385368E-
 
            Note that for a sampling or comparison run involving frames not
            supported by CKs or binary PCK the program has no way of
            automatically picking the frames and time boundaries and
            requires users to specify the frames and time boundaries
            explicitly on the command line.
 
