| srfs2c_c |
|
Table of contents
Procedure
srfs2c_c ( Surface and body strings to surface ID code )
void srfs2c_c ( ConstSpiceChar * srfstr,
ConstSpiceChar * bodstr,
SpiceInt * code,
SpiceBoolean * found )
AbstractTranslate a surface string, together with a body string, to the corresponding surface ID code. The input strings may contain names or integer ID codes. Required_ReadingDSK NAIF_IDS KeywordsCONVERSION DSK ID NAME STRING SURFACE Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- srfstr I Surface name or ID string. bodstr I Body name or ID string. code O Integer surface ID code. found O Flag indicating whether surface ID was found. Detailed_Input
srfstr is a string designating a surface. `srfstr' may contain
a surface name or a string representation of the
surface's integer ID code.
If, for the body specified by `bodstr', multiple surface
names are associated with one surface ID code, then any
of these names may be used as the value of `srfstr'.
Case and leading and trailing blanks in a surface name
are not significant. Sequences of consecutive embedded
blanks are considered equivalent to a single blank.
For example, all of the strings below are considered
to be equivalent:
"MGS MOLA 128 PIXEL/DEG"
"MGS MOLA 128 pixel/deg"
"MGS MOLA 128 PIXEL/DEG "
"MGS MOLA 128 PIXEL/DEG"
" MGS MOLA 128 PIXEL/DEG"
However,
"MGSMOLA 128PIXEL/DEG"
is not equivalent to the names above.
bodstr is a string designating the body associated with the
input surface string. `bodstr' may contain a body name
or a string representation of the body's integer ID
code. For example, `bodstr' may contain
"1000012"
instead of
"67P/CHURYUMOV-GERASIMENKO (1969 R1)"
Case and leading and trailing blanks in a name are not
significant. The treatment of blanks in `bodstr' is the
same as for `srfstr'.
Detailed_Output
code is integer ID code of the surface designated by
`srfstr', for the body designated by `bodstr', if for this
body an association exists between the input surface
string and a surface ID code. `code' is defined if and
only if the output flag `found' is SPICETRUE.
found is a logical flag that is SPICETRUE if a surface code
corresponding to the input strings was found and
SPICEFALSE otherwise.
ParametersNone. Exceptions
1) If the input surface string does not map to an ID code
and does not represent an integer, the output `code' is
undefined and the output `found' is set to SPICEFALSE.
This case is not treated as an error.
2) If the input body string does not map to an ID code and does
not represent an integer, the output `code' is undefined and
the output `found' is set to SPICEFALSE.
This case is not treated as an error.
3) If any of the `srfstr' or `bodstr' input string pointers is
null, the error SPICE(NULLPOINTER) is signaled.
4) If any of the `srfstr' or `bodstr' input strings has zero
length, the error SPICE(EMPTYSTRING) is signaled.
Files
Surface name-to-ID mappings may be defined at run time by loading
text kernels containing kernel variable assignments of the form
NAIF_SURFACE_NAME += ( <surface name 1>, ... )
NAIF_SURFACE_CODE += ( <surface code 1>, ... )
NAIF_SURFACE_BODY += ( <body code 1>, ... )
Above, the Ith elements of the lists on the assignments' right
hand sides together define the Ith surface name/ID mapping.
The same effect can be achieved using assignments formatted as
follows:
NAIF_SURFACE_NAME += <surface name 1>
NAIF_SURFACE_CODE += <surface code 1>
NAIF_SURFACE_BODY += <body code 1>
NAIF_SURFACE_NAME += <surface name 2>
NAIF_SURFACE_CODE += <surface code 2>
NAIF_SURFACE_BODY += <body code 2>
...
Note the use of the
+=
operator; this operator appends to rather than overwrites the
kernel variable named on the left hand side of the assignment.
Particulars
Surfaces are always associated with bodies (which usually are
ephemeris objects). For any given body, a mapping between surface
names and surface ID codes can be established.
Bodies serve to disambiguate surface names and ID codes: the set
of surface names and surface ID codes for a given body can be
thought of as belonging to a name space. A given surface ID code
or surface name may be used for surfaces of multiple bodies,
without conflict.
Associations between surface names and ID codes are always made
via kernel pool assignments; there are no built-in associations.
srfs2c_c is one of four related functions:
srfs2c_c Surface string and body string to surface ID code
srfscc_c Surface string and body ID code to surface ID code
srfc2s_c Surface ID code and body ID code to surface string
srfcss_c Surface ID code and body string to surface string
srfs2c_c, srfc2s_c, srfscc_c, and srfcss_c perform translations between
surface strings and their corresponding integer ID codes.
Refer to naif_ids.req for details concerning adding new surface
name/code associations at run time by loading text kernels.
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) Suppose a text kernel has been loaded that contains
the following assignments:
NAIF_SURFACE_NAME += ( 'MGS MOLA 64 pixel/deg',
'MGS MOLA 128 pixel/deg',
'PHOBOS GASKELL Q512' )
NAIF_SURFACE_CODE += ( 1, 2, 1 )
NAIF_SURFACE_BODY += ( 499, 499, 401 )
Translate each surface and body string pair to the
associated surface ID code. Also perform a translation
for a surface name having no matching ID and for
a body string having no matching body ID code.
Use the meta-kernel shown below to define the required SPICE
kernel variables.
KPL/MK
File: srfs2c_ex1.tm
This meta-kernel is intended to support operation of SPICE
example programs. The file contents shown here should not be
assumed to contain adequate or correct versions of data
required by SPICE-based user applications.
\begindata
NAIF_SURFACE_NAME += ( 'MGS MOLA 64 pixel/deg',
'MGS MOLA 128 pixel/deg',
'PHOBOS GASKELL Q512' )
NAIF_SURFACE_CODE += ( 1, 2, 1 )
NAIF_SURFACE_BODY += ( 499, 499, 401 )
\begintext
End of meta-kernel
Example code begins here.
/.
Program srfs2c_ex1
./
#include <stdio.h>
#include "SpiceUsr.h"
int main()
{
/.
Local constants
./
#define BDNMLN 37
#define SFNMLN SPICE_SRF_SFNMLN
#define NCASE 8
/.
Local variables
./
SpiceBoolean found;
static SpiceChar bodstr [NCASE][BDNMLN] =
{ "MARS", "PHOBOS", "MARS",
"499", "PHOBOS", "499",
"MARS", "ZZZ" };
static SpiceChar srfstr [NCASE][SFNMLN] =
{ "MGS MOLA 64 pixel/deg",
"PHOBOS GASKELL Q512",
"MGS MOLA 128 pixel/deg",
"MGS MOLA 64 pixel/deg",
"1",
"2",
"ZZZ",
"1" };
static SpiceChar tf [2][6] =
{ "false", "true" };
SpiceChar * meta;
SpiceInt i;
SpiceInt surfid;
meta = "srfs2c_ex1.tm";
furnsh_c ( meta );
printf ( "\n" );
for ( i = 0; i < NCASE; i++ )
{
srfs2c_c ( srfstr[i], bodstr[i], &surfid, &found );
printf ( "surface string = %s\n"
"body string = %s\n"
"surface ID found = %s\n",
srfstr[i],
bodstr[i],
tf[found] );
if ( found )
{
printf ( "surface ID = %d\n", surfid );
}
printf ( "\n" );
}
return ( 0 );
}
When this program was executed on a Mac/Intel/cc/64-bit
platform, the output was:
surface string = MGS MOLA 64 pixel/deg
body string = MARS
surface ID found = true
surface ID = 1
surface string = PHOBOS GASKELL Q512
body string = PHOBOS
surface ID found = true
surface ID = 1
surface string = MGS MOLA 128 pixel/deg
body string = MARS
surface ID found = true
surface ID = 2
surface string = MGS MOLA 64 pixel/deg
body string = 499
surface ID found = true
surface ID = 1
surface string = 1
body string = PHOBOS
surface ID found = true
surface ID = 1
surface string = 2
body string = 499
surface ID found = true
surface ID = 2
surface string = ZZZ
body string = MARS
surface ID found = false
surface string = 1
body string = ZZZ
surface ID found = false
RestrictionsNone. Literature_ReferencesNone. Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) B.V. Semenov (JPL) E.D. Wright (JPL) Version
-CSPICE Version 1.0.1, 01-NOV-2021 (JDR) (NJB)
Edited the header to comply with NAIF standard.
Updated description of "srfstr" to indicate that any
surface name alias may be used.
-CSPICE Version 1.0.0, 22-JAN-2016 (NJB) (BVS) (EDW)
Index_Entriessurface string and body string to surface ID code |
Fri Dec 31 18:41:13 2021