| ekssum_c |
|
Table of contents
Procedure
ekssum_c ( EK, return segment summary )
void ekssum_c ( SpiceInt handle,
SpiceInt segno,
SpiceEKSegSum * segsum )
AbstractReturn summary information for a specified segment in a specified EK. Required_ReadingEK KeywordsEK UTILITY Brief_I/OVARIABLE I/O DESCRIPTION -------- --- -------------------------------------------------- handle I Handle of EK. segno I Number of segment to be summarized. segsum O EK segment summary. Detailed_Input
handle is an EK file handle specifying the EK containing
the segment to be summarized.
segno is the number of the segment whose summary is
desired. Segments are numbered from 0 to nseg-1,
where nseg is the count of segments in the file.
Detailed_Output
segsum is a pointer to an EK segment summary. The summary is
of type EKSegSum. The structure contains the
following members:
tabnam The name of the table to which the
segment belongs.
nrows The number of rows in the segment.
ncols The number of columns in the segment.
cnames An array of names of columns in the
segment. Column names may contain
as many as SPICE_EK_CNAMSZ characters.
The array contains room for
SPICE_EK_MXCLSG column names.
cdescrs An array of column attribute
descriptors of type SpiceEKAttDsc.
The array contains room for
SPICE_EK_MXCLSG descriptors. The Ith
descriptor corresponds to the column
whose name is the Ith element of the
array cnames.
The column attribute descriptors have the following
members:
cclass: Column class code.
dtype: Data type code: has type
SpiceEKDataType.
strlen: String length. Applies to SPICE_CHR
type. Value is SPICE_EK_VARSIZ for
variable-length strings.
size: Column entry size; this is the number
of array elements in a column entry.
The value is SPICE_EK_VARSIZ for
variable-size columns.
indexd: Index flag; value is SPICETRUE if the
column is indexed, SPICEFALSE
otherwise.
nullok: Null flag; value is SPICETRUE if the
column may contain null values,
SPICEFALSE otherwise.
ParametersSee the -Restrictions section. Exceptions
1) If `handle' is invalid, an error is signaled by a routine in the
call tree of this routine. The output arguments will not be
modified.
2) If `segno' is not the index of an existing segment in the
specified file, the error SPICE(INDEXOUTOFRANGE) is signaled by
a routine in the call tree of this routine. The output arguments
will not be modified.
3) If an I/O error occurs while attempting to obtain summary
information for the specified segment, the error is signaled
by a routine in the call tree of this routine. The output
arguments may be modified in this case.
FilesThis routine provides summary information for segments belonging to a binary EK file. ParticularsThis routine supports the function of summarizing a binary EK file, allowing NAIF Toolkit users to determine whether it contains data of interest. 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) Dump the attributes of the segments in a specified EK.
Example code begins here.
/.
ekssum_ex1
./
#include <stdio.h>
#include "SpiceUsr.h"
int main()
{
/.
Constants
./
#define FILSIZ 256
SpiceChar ek [FILSIZ];
static SpiceChar chrTypes [4][5] = { "CHR",
"DP",
"INT",
"TIME" };
SpiceEKSegSum segsum;
SpiceInt handle;
SpiceInt i;
SpiceInt nseg;
SpiceInt segno;
prompt_c ( "Enter name of EK file > ", FILSIZ, ek );
/.
Open the EK for read access and get the number of
segments it contains.
./
ekopr_c ( ek, &handle );
nseg = eknseg_c ( handle );
/.
Loop through the segments, dumping the desired
summary information for each one.
./
printf ( "\n"
"Segment summary for file %s\n\n",
ek );
for ( segno = 0; segno < nseg; segno++ )
{
ekssum_c ( handle, segno, &segsum );
printf ( "=============================="
"=============================="
"\n"
"Table containing segment: %s\n"
"\n"
"Number of rows: %d\n"
"Number of columns: %d\n"
"\n"
"Column names and attributes: \n"
"\n",
segsum.tabnam,
segsum.nrows,
segsum.ncols );
for ( i = 0; i < segsum.ncols; i++ )
{
printf ( "\n"
"Column: %s\n"
"\n"
"Data type: %s\n",
segsum.cnames[i],
chrTypes[ segsum.cdescrs[i].dtype ] );
if ( segsum.cdescrs[i].size >= 0 )
{
printf ( "Dimension: %d\n",
segsum.cdescrs[i].size );
}
else
{
printf ( "Dimension: Variable\n" );
}
if ( segsum.cdescrs[i].dtype == SPICE_CHR )
{
if ( segsum.cdescrs[i].strlen >= 0 )
{
printf ( "String length: %d\n",
segsum.cdescrs[i].strlen );
}
else
{
printf ( "String length: Variable\n" );
}
}
if ( segsum.cdescrs[i].indexd )
{
printf ( "Indexed\n" );
}
if ( segsum.cdescrs[i].nullok )
{
printf ( "Nulls allowed\n" );
}
printf ( "\n" );
}
printf ( "\n"
"=============================="
"=============================="
"\n" );
}
return ( 0 );
}
When this program was executed on a Mac/Intel/cc/64-bit
platform, using the EK file named dif_cmdict_128_20050620.bdb
to load the Deep Impact spacecraft subsystem commands dictionary,
the output was:
Enter name of EK file > dif_cmdict_128_20050620.bdb
Segment summary for file dif_cmdict_128_20050620.bdb
============================================================
Table containing segment: DIF_COMMANDS
Number of rows: 5798
Number of columns: 7
Column names and attributes:
Column: SUBSYSTEM
Data type: CHR
Dimension: 1
String length: 32
Indexed
Column: COMMAND
Data type: CHR
Dimension: 1
String length: 32
Indexed
Column: PARAMETER_NAME
Data type: CHR
Dimension: 1
String length: 32
Indexed
Column: PARAMETER_INDEX
Data type: INT
Dimension: 1
Indexed
Column: PARAMETER_TYPE
Data type: CHR
Dimension: 1
String length: 32
Nulls allowed
Column: PARAMETER_RANGE
Data type: CHR
Dimension: Variable
String length: 80
Nulls allowed
Column: DESCRIPTION
Data type: CHR
Dimension: Variable
String length: 80
============================================================
Restrictions
1) Many parameters used internally in this routine are from the
Fortran SPICELIB include files ekcoldsc.inc and eksegdsc.inc.
The parameters used in this routine must be kept in sync with
those used in SPICELIB.
Literature_ReferencesNone. Author_and_InstitutionN.J. Bachman (JPL) J. Diaz del Rio (ODC Space) Version
-CSPICE Version 1.1.1, 10-AUG-2021 (JDR)
Edited the header to comply with NAIF standard.
Added the solution to the example when using a Deep Impact EK kernel.
Reformatted example's output.
-CSPICE Version 1.1.0, 12-JUL-1999 (NJB)
Now calls zzeksinf_ instead of ekssum_ to get summary
information. This enables retrieval of column classes and
simplifies the code as well.
Changed arrays of SpiceBoolean flags passed to ekssum_ to
data type logical. Changed name of "class" member of structure
SpiceEKSegSum to "cclass." The name "class" is a C++ keyword
and prevented clean integration into C++ code.
-CSPICE Version 1.0.0, 17-FEB-1999 (NJB)
Index_Entriesreturn EK segment summary |
Fri Dec 31 18:41:06 2021