How to read JPL CD-ROM for DE200/405/406 by "C" on PC

This page explain the method to read and use the JPL CD-ROM for DE200/405/406.The software attached in this page is for C compiler in MS VC++ Ver.6.

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Section 1 How to get CD-ROM

At first, you have to perches the CD-ROM. The CD-ROM is provided by
Willmann-Bell, Inc. You can get though from the following web site.
JPL PLANETARY AND LUNAR EPHEMERIDES ON CD-ROMby Standish, et. al. $24.95

The each ephemeris support following terms.

DE200 : (includes nutations but not librations)
JED 2305424.5 (1599 DEC 09) to JED 2513360.5 (2169 MAR 31)

DE405 : (includes both nutations and librations)
JED 2305424.50 (1599 DEC 09) to JED 2525008.50 (2201 FEB 20)

DE406 : the New "JPL Long Ephemeris" (includes neither nutations nor librations)
JED 0625360.50 (-3000 FEB 23) to 2816912.50 (+3000 MAY 06)

The size of the each ephemeris is as follows.

Ephemeris items　　　　　　　　　　DE200　　DE405　　DE406
---------------　　　　　　　　　　-----　　-----　　-----
UNIX binary　　　　　　　　　　　　　:　　55Mb 　　62 Mb　　199 Mb
ASCII (each 20-year block)　:　　　　5.2Mb　　6.4Mb　　 -

There are several problems to use CD-ROM.
1)The attached source cord to use CD-ROM is Fortran only.
2)The ephemeris data is stored in unix format.
3)The ascii format data is attached, but conversion program is fortran.
4)No ascii data for DE406.

Therefore following step is necessary to use the CD-ROM on the PC.
1)The data conversion form Unix format to Dos format.
2)The C code software to use the CD-ROM.
The following section explain the above.

Section 2 The data conversion from Unix format to dos format

The following source code convert the unix file(unix.xxx) to dos
file (dos.xxx).（xxx is 200, 405 or 406）
Please check the Hard disk size before running the software,Because
the software will create same size of dos file.

　　Source file for file conversion"file_convert.zip"

Section 3 Check of the converted file

The Fortran version of test program and calculation results file
(testpo.xxx) to check the installation of CD-ROM is attached in the CD-ROM.
The C version of the test program is also available in the following site.
Index of /ephem/export/C-versions/kourosh
This file is provided by Mr. K. Arfa-Kaboodvand.

However this "C version" software also use the special data format,
this program cannot read the converted file (dos.xxx).
It will require the modification.
The modified source code is attached below.
Converted file test program"test.zip"

Then we can check the converted file and calculation routine in test.c
with following three files.
1)dos.xxx file(Converted file in section 2)
2)executable file of test.c file (after compile)
3)testpo.xxx (attached in the CD-ROM)

If the test.exe file finish without error, the converter file and
the calculation routine in test.c is correct.

Section 4 Calculation of the rectangular components

The Fortran source code for calculation of the rectangular components
are attached in the CD-ROM.
The C version of the program is also available in the following site.
Index of /ephem/export/C-versions/kourosh
This file is provided by Mr. K. Arfa-Kaboodvand.
The following source code is modified from the above file to read
des.xxx data file.
By using the following files, we can get the rectangular components.
1)test1.exe file compiled from test1.c.
2)dos.xxx file.
The calculation results for earth is also attached.

source code for rectangular components"test1.zip"
Example for earth(at 1999/01/00 0hTDB)"test1.txt"

Section 5 Calculation of coordinates for sun, moon, planets

The CD-ROM provides only rectangular components. Therefore the additional
calculation is necessary. The following file provide the coordinates of the
sun, moon and planets.
Please use with following condition.
1)Executable software compiled from"jpl_eph.zip"
2)dos.xxx file

　　Cordinates calculation software"jpl_eph.zip(21kbytes)"
　　Example for Macury (at 1999/01/01 0hTDB)"test.txt"

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