| spkopa_c |
|
Table of contents
Procedure
spkopa_c ( SPK open for addition )
void spkopa_c ( ConstSpiceChar * file,
SpiceInt * handle )
AbstractOpen an existing SPK file for subsequent write. Required_ReadingSPK KeywordsSPK Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- file I The name of an existing SPK file. handle O Handle attached to the SPK file opened to append. Detailed_Input
file is the name of an existing SPK file to which
you wish to append additional SPK segments.
Detailed_Output
handle is the DAF integer handle that refers to the SPK file
opened for appending. `handle' is required by any of the
SPK writing routines.
ParametersNone. Exceptions
If any of the following exceptions occur, `handle' will be returned
with the value 0.
1) If the file specified does not exist, the error
SPICE(FILENOTFOUND) is signaled by a routine in the call tree
of this routine.
2) If the file specified is not an SPK file, the error
SPICE(FILEISNOTSPK) is signaled by a routine in the call tree
of this routine.
3) If the specified SPK file cannot be opened for writing, an
error is signaled by a routine in the call tree of this
routine.
4) If the specified SPK file uses a non-native binary file
format, an error is signaled by a routine in the call tree of
this routine.
5) If the specified SPK file is corrupted or otherwise invalid,
an error is signaled by a routine in the call tree of this
routine.
6) If the `file' input string pointer is null, the error
SPICE(NULLPOINTER) is signaled.
7) If the `file' input string has zero length, the error
SPICE(EMPTYSTRING) is signaled.
FilesNone. ParticularsThis file provides an interface for opening existing SPK files for the addition of SPK segments. If you need to open an new SPK file for writing, call the routine spkopn_c. Examples
The numerical results shown for this example 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) This example demonstrates how to add a new segment to an
SPK type 5 kernel.
For this example, we will first create an SPK type 5 kernel
containing only one segment, given a time-ordered set of
discrete states and epochs, and the gravitational parameter
of a central body.
Then, we will reopen the SPK and add a second segment. The
example below shows one set of calls that you could perform
to make the addition. Obviously, there is no need to close
and re-open the file in order to add multiple segments. It is
done in this example to demonstrate the use of spkopa_c.
Note that you could add segments of other data types by
replacing the call to spkw05_c with a suitably modified call to
another SPK writing routine.
Example code begins here.
/.
Program spkopa_ex1
./
#include "SpiceUsr.h"
int main( )
{
/.
Define the segment identifier parameters.
./
#define SPK5 "spkopa_ex1.bsp"
#define REF "J2000"
#define GMSUN 132712440023.310
#define BODY 3
#define CENTER 10
#define NSTATS 9
/.
Local variables.
./
SpiceChar * ifname;
SpiceChar * segid;
SpiceDouble first;
SpiceDouble last;
SpiceInt handle;
SpiceInt ncomch;
/.
Define the states and epochs.
./
SpiceDouble states [NSTATS][6] = {
{101.0, 201.0, 301.0, 401.0, 501.0, 601.0},
{102.0, 202.0, 302.0, 402.0, 502.0, 602.0},
{103.0, 203.0, 303.0, 403.0, 503.0, 603.0},
{104.0, 204.0, 304.0, 404.0, 504.0, 604.0},
{105.0, 205.0, 305.0, 405.0, 505.0, 605.0},
{106.0, 206.0, 306.0, 406.0, 506.0, 606.0},
{107.0, 207.0, 307.0, 407.0, 507.0, 607.0},
{108.0, 208.0, 308.0, 408.0, 508.0, 608.0},
{109.0, 209.0, 309.0, 409.0, 509.0, 609.0} };
SpiceDouble epoch1 [NSTATS] = { 100.0, 200.0, 300.0,
400.0, 500.0, 600.0,
700.0, 800.0, 900.0 };
SpiceDouble epoch2 [NSTATS] = { 1100.0, 1200.0, 1300.0,
1400.0, 1500.0, 1600.0,
1700.0, 1800.0, 1900.0 };
/.
Set the start and stop times of interval covered by
the first segment.
./
first = epoch1[0];
last = epoch1[NSTATS-1];
/.
`ncomch' is the number of characters to reserve for the
kernel's comment area. This example doesn't write
comments, so set to zero.
./
ncomch = 0;
/.
Internal file name and segment ID.
./
ifname = "Type 5 SPK internal file name.";
segid = "SPK type 5 test segment #1";
/.
Open a new SPK file.
./
spkopn_c ( SPK5, ifname, ncomch, &handle );
/.
Write the segment.
./
spkw05_c ( handle, BODY, CENTER, REF, first, last,
segid, GMSUN, NSTATS, states, epoch1 );
/.
Close the SPK file.
./
spkcls_c ( handle );
/.
At this point we have an existing SPK type 5 kernel
that contains a single segment. Let's now demonstrate
the use of spkopa_c.
Open the an existing SPK file for subsequent write.
./
spkopa_c ( SPK5, &handle );
/.
Set the start and stop times of interval covered by
the second segment, and the segment ID.
./
first = epoch2[0];
last = epoch2[NSTATS-1];
segid = "SPK type 5 test segment #2";
/.
Now write the second segment. Use the same set of
states time-ordered set of discrete states and the
gravitational parameter. Set the epochs to be `epoch2'.
./
spkw05_c ( handle, BODY, CENTER, REF, first, last,
segid, GMSUN, NSTATS, states, epoch2 );
/.
Finally, close the file.
./
spkcls_c ( handle );
return ( 0 );
}
When this program is executed, no output is presented on
screen. After run completion, a new SPK type 5, with two
segments, exists in the output directory.
RestrictionsNone. Literature_ReferencesNone. Author_and_InstitutionJ. Diaz del Rio (ODC Space) F.S. Turner (JPL) Version
-CSPICE Version 1.0.1, 05-AUG-2021 (JDR)
Edited the header to comply with NAIF standard. Added complete
code example.
Added entries #3 to #5 in -Exceptions section.
-CSPICE Version 1.0.0, 16-MAR-1999 (FST)
Index_EntriesOpen an existing SPK file for adding segments |
Fri Dec 31 18:41:12 2021