| pcklof_c |
|
Table of contents
Procedure
pcklof_c ( PCK, load binary file )
void pcklof_c ( ConstSpiceChar * fname,
SpiceInt * handle )
AbstractLoad a binary PCK file for use by the readers. Return the handle of the loaded file which is used by other PCK routines to refer to the file. Required_ReadingDAF PCK KeywordsFILES PCK Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- fname I Name of the file to be loaded. handle O Loaded file's handle. Detailed_Inputfname is the character name of the file to be loaded. Detailed_Output
handle is the integer handle assigned to the file upon loading.
Other PCK routines will subsequently use this number to
refer to the file.
ParametersNone. Exceptions
1) If an attempt is made to open more DAF files than is
specified by the parameter FTSIZE in DAF system, an error
is signaled by a routine in the call tree of this routine.
2) If an attempt is made to load more files than is specified by
the parameter FTSIZE in the PCK subsystem, and if the DAF
system has room to load another file, the error
SPICE(PCKFILETABLEFULL) is signaled by a routine in the call
tree of this routine. The current setting of FTSIZE does not
allow this situation to arise: the DAF system will trap the
error before this routine has the chance.
3) This routine makes use of DAF file system routines and is
subject to all of the constraints imposed by the DAF file
system. See the DAF Required Reading daf.req or individual DAF
routines for details.
4) If the `fname' input string pointer is null, the error
SPICE(NULLPOINTER) is signaled.
5) If the `fname' input string has zero length, the error
SPICE(EMPTYSTRING) is signaled.
FilesA file specified by `fname', to be loaded. The file is assigned a handle by pcklof_c, which will be used by other routines to refer to it. ParticularsIf there is room for a new file in the file table, pcklof_c creates an entry for it, and opens the file for reading. Also, if the file table is empty, pcklof_c initializes it. Examples
The numerical results shown for these examples may differ across
platforms. The results depend on the SPICE kernels used as
input, the compiler and supporting libraries, and the machine
specific arithmetic implementation.
1) Load a high precision PCK file for the Earth and compute the
position transformation matrix from ITRF93 to J2000 at
2000 Jan 01 12:00:00 TDB.
Use the PCK kernel below to load the required triaxial
ellipsoidal shape model and orientation data for the Earth.
earth_720101_070426.bpc
Example code begins here.
/.
Program pcklof_ex1
./
#include <stdio.h>
#include "SpiceUsr.h"
int main()
{
/.
Local variables.
./
SpiceDouble xform [3][3];
SpiceInt handle;
SpiceInt i;
/.
Open the PCK for read access. This call may be replaced (as
recommended by NAIF) by furnsh_c.
./
pcklof_c ( "earth_720101_070426.bpc", &handle );
/.
Find the position transformation matrix at
2000 Jan 01 12:00:00 TDB
which corresponds to ephemeris time 0.
./
pxform_c( "ITRF93", "J2000", 0.0, xform );
/.
Display the results.
./
printf ("Position transformation from ITRF93 to J2000 frame:\n\n" );
for ( i = 0; i < 3; i++ )
{
printf("%19.10f %19.10f %19.10f\n",
xform[i][0], xform[i][1], xform[i][2] );
}
/.
Close the PCK file. This call may be replaced (as
recommended by NAIF) by unload_c.
./
pckuof_c ( handle );
return ( 0 );
}
When this program was executed on a Mac/Intel/cc/64-bit
platform, the output was:
Position transformation from ITRF93 to J2000 frame:
0.1769805935 0.9842143409 -0.0000251874
-0.9842143410 0.1769805928 -0.0000274792
-0.0000225878 0.0000296531 0.9999999993
2) The following example extracts the first 20 lines of the
comment area of a binary PCK, displaying the comments on
the terminal screen.
Example code begins here.
/.
Program pcklof_ex2
./
#include <stdio.h>
#include "SpiceUsr.h"
int main()
{
/.
Local parameters.
./
#define FILSIZ 256
#define LINLEN 1001
#define BUFFSZ 20
/.
Local variables.
./
SpiceBoolean done;
SpiceChar pcknam [FILSIZ];
SpiceChar buffer [BUFFSZ][LINLEN];
SpiceInt handle;
SpiceInt i;
SpiceInt n;
prompt_c ( "Enter name of PCK > ", FILSIZ, pcknam );
/.
Open the PCK for read access. This operation could have
been done with dafopr_c.
./
pcklof_c ( pcknam, &handle );
/.
Extract up to 20 lines from the comment area of the
loaded PCK file and display them on the terminal screen.
./
dafec_c ( handle, BUFFSZ, LINLEN, &n, buffer, &done );
for ( i = 0; i < n; i++ )
{
printf ( "%s\n", buffer[i] );
}
/.
Close the PCK file. This operation could have been done
with dafcls_c.
./
pckuof_c ( handle );
return ( 0 );
}
When this program was executed on a Mac/Intel/cc/64-bit
platform, using the hight precision PCK file for the Earth named
earth_720101_070426.bpc as input PCK file, the output was:
Enter name of PCK > earth_720101_070426.bpc
Binary "High Accuracy" Earth PCK File
======================================
Created 27-APR-2007 by NJB (NAIF/JPL)
Original file name: earth_720101_070426.bpc
Data Source
Input file: EOP file 2007_04_26_long.eop
(Copied from WWW URL
http://epic.jpl.nasa.gov/nav/eop/latest.long)
Coverage
ET Start time: 1972 JAN 01 00:00:42.183
ET Stop time: 2007 APR 26 00:01:05.185
UTC Epoch of last datum: 26-APR-2007
RestrictionsNone. Literature_ReferencesNone. Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) E.D. Wright (JPL) K.S. Zukor (JPL) Version
-CSPICE Version 2.1.0, 01-NOV-2021 (JDR)
Changed input argument name "filename" to "fname" for
consistency with other routines.
Edited the header with NAIF standard. Added complete
code examples.
Moved the reference to DAF required reading from
-Literature_References to -Required_Reading.
-CSPICE Version 2.0.1, 20-MAR-1998 (EDW)
Minor correction to header.
-CSPICE Version 2.0.0, 08-FEB-1998 (NJB)
Input argument "filename" was changed to type ConstSpiceChar *.
Re-implemented routine without dynamically allocated, temporary
strings.
-CSPICE Version 1.0.0, 25-OCT-1997 (EDW) (KSZ)
Index_Entriesload PCK file Link to routine pcklof_c source file pcklof_c.c |
Fri Dec 31 18:41:10 2021