Index Page DSKEXP User's Guide

## Table of Contents

       DSKEXP User's Guide
          Abstract
          Summary
          DSKEXP output formats
          Running DSKEXP
          Examples

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# DSKEXP User's Guide

Last revised on 2015 APR 07 by N. J. Bachman.

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## Abstract

DSKEXP is a command-line program that exports data from DSK files to text files.

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## Summary

DSKEXP enables SPICE Toolkit users to ``export'' data from a DSK file to any of a variety of simple, easily parsed text formats. This capability enables users to easily transform DSK files into formats required by other applications; it also makes it easy to inspect the data in a DSK file.

DSKEXP currently is limited to processing type 2 (plate model) DSK segments.

If the input DSK file contains multiple segments, an output text file will be created for each segment.

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## DSKEXP output formats

Output files created by DSKEXP are usable as input data files by the SPICE program MKDSK. The supported formats are:

`1.` Plate-vertex table. The MKDSK code for this format is 1. The output file format is

                <vertex count NV>
                1   <vertex 1  X value><Y value><Z value>
                      ...
                NV  <vertex NV X value><Y value><Z value>
                <plate count NP>
                1  <plate 1  vertex 1 ID><vertex 2 ID><vertex 3 ID>
                      ...
                NP <plate NP vertex 1 ID><vertex 2 ID><vertex 3 ID>

`2.` Vertex-facet table. This format is also called ``obj'' format. The MKDSK code for this format is 3. The output file format is

                 v <vertex 1  X value><Y value><Z value>
                      ...
                 v <vertex NV X value><Y value><Z value>
                 f <plate 1  vertex 1 ID><vertex 2 ID><vertex 3 ID>
                      ...
                 f <plate NP vertex 1 ID><vertex 2 ID><vertex 3 ID>

`` In the diagram above, NV and NP are the vertex and plate counts, respectively.

`3.` Rosetta/OSIRIS ``ver'' format. The MKDSK code for this format is 4. The output file format is

                <vertex count NV> <plate count NP>
                  <vertex 1  X value><Y value><Z value>
                      ...
                  <vertex NV X value><Y value><Z value>
                3
                  <plate 1  vertex 1 ID><vertex 2 ID><vertex 3 ID>
                      ...
                3
                  <plate NP vertex 1 ID><vertex 2 ID><vertex 3 ID>

The Gaskell ICQ format (MKDSK code 2) is not supported as an export format.

See the MKDSK User's Guide for further information on these text file formats.

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## Running DSKEXP

The command syntax for DSKEXP is

       dskexp   -dsk    <dsk>
                -text   <output name>
                -format <MKDSK format code/name>
               [-prec   <# of vertex mantissa digits (1:17)>]

The parameters other than the output precision must be present in the command.

The value associated with the keyword

       -format

specifies the output file format. All of the supported output formats are valid MKDSK input file formats. See the section ``DSKEXP output formats'' above for further information.

Output formats may be specified by name or by integer code.

If the input file contains multiple segments, an output file will be written for each segment. The file for the nth segment, where n is greater than 1, will have the string

       _<n-1>

appended to the output file name specified on the command line. For example, if the input DSK contains multiple segments and if the specified output file name is

       phobos.plt

then the file for the first segment will have that name, the file for the second segment will be named

       phobos.plt_1

and so on.

The optional output precision specification allows users to limit the precision of the double precision numbers representing components of plate model vertices. Reducing the output precision can significantly reduce the size of the output file. By default, full precision (17 mantissa digits) is used.

The command

       dskexp

(without parameters) causes DSKEXP to dump a usage summary, as do the commands

       dskexp -usage
       dskexp -u
       dskexp -help
       dskexp -h

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## Examples

`1.` Create a vertex-facet format output file. This example uses default precision for the output vertices.

                dskexp -dsk phobos.bds -text phobos.obj -format vertex-facet

`2.` Create a vertex-facet format output file. Use 9-digit mantissas for the vertices. The format name "obj" can be used to indicate vertex-facet format.

                dskexp -dsk phobos.bds -text phobos.obj -format obj -prec 9

`3.` Create a vertex-facet format output file. Use 9-digit mantissas for the vertices. The format code 3 can be used to indicate vertex-facet format.

                dskexp -dsk phobos.bds -text phobos.obj -format 3 -prec 9

`4.` Create a plate-vertex format output file. This example uses default precision for the output vertices.

                dskexp -dsk phobos.bds -text phobos.obj -format plate-vertex

`5.` Create a plate-vertex format output file. Use the integer code for this format.

                dskexp -dsk phobos.bds -text phobos.obj -format 1

`6.` Create a Rosetta "ver" format output file.

                dskexp -dsk phobos.bds -text phobos.obj -format ver

`7.` Create a Rosetta "ver" format output file. Use the integer code for this format.

                dskexp -dsk phobos.bds -text phobos.obj -format 4