Table of contents
valid_c ( Validate a set )
void valid_c ( SpiceInt size,
SpiceCell * a )
Create a valid SPICE set from a SPICE Cell of any data type.
VARIABLE I/O DESCRIPTION
-------- --- --------------------------------------------------
size I Size (maximum cardinality) of the set.
n I Initial no. of (possibly non-distinct) elements.
a I-O Set to be validated.
size is the maximum cardinality (number of elements) of the set.
`size' must not exceed the declared size of the set's data
n is the number of (possibly non-distinct) elements initially
contained in the set's data array. `n' cannot be greater than
the size of the set.
a is a SPICE set.
On input, `a' contains `n' elements.
`a' must be declared as a character, double precision or
CSPICE provides the following macros, which declare and
initialize the cell
SPICECHAR_CELL ( a, ASZ, AMLEN );
SPICEDOUBLE_CELL ( a, ASZ );
SPICEINT_CELL ( a, ASZ );
where ASZ is the maximum capacity of `a' and AMLEN is the
maximum length of any member in the character cell.
a on output, is a valid set created from the input set.
To create a valid set, the elements are ordered, and duplicate
elements are removed. The set's size and cardinality members
are assigned their correct values.
The set is ready for use with other set routines.
When validating a character set, trailing blanks are not
considered significant in process of sorting and removing
duplicates. Trailing blanks are not preserved on output.
1) If the size of the set is too small to hold the set BEFORE
validation, the error SPICE(INVALIDSIZE) is signaled by a routine
in the call tree of this routine. The set `a' is not modified.
2) If the cell argument does not have a recognized data type, the
error SPICE(NOTSUPPORTED) is signaled.
3) If the cell argument is of type SpiceChar and the string length
associated with it is non-positive or too short to be usable when
constructing the equivalent SPICE character cell required by
the wrapped SPICELIB routine, an error is signaled by a routine
in the call tree of this routine.
Because a set is ordered and contains distinct values, to create a
set from a cell, it is necessary to sort the data array and remove
duplicates. Once the array has been sorted, duplicate elements
(adjacent after sorting) are removed. The size and cardinality of
the set are initialized, and the set is ready to go.
This routine is typically used to create a SPICE set from a SPICE
cell whose array which has been initialized via calls the appndX_c
routines, or through compile-time array initializers, or I/O
statements. The resulting set can then be used with the other set
When a set is constructed from a large set of unordered values,
it is far more efficient to append the values to the set and
then validate the set, than to build up the set via calls to the
insrtX_c routines. The latter sort the set and remove duplicates
on each insertion.
Because validation is done in place, there is no chance of
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) Build a double precision cell via a series of calls to appndd_c.
Create a set from this set by calling valid_c.
Example code begins here.
SETSIZ is the maximum capacity of the set.
#define SETSIZ 1000000
INISIZ will be the initial number of elements in the set.
#define INISIZ 10
Declare the set.
SPICEDOUBLE_CELL ( dpSet, SETSIZ );
Other local variables.
Initialize the cell's data array. We use bogus values to
simplify the example.
printf( "Input data array:\n" );
for ( i = 0; i < INISIZ; i++ )
appndd_c ( (SpiceDouble)(-i), &dpSet );
printf( " %3.1f", (SpiceDouble)(-i) );
printf( "\n\n" );
Validate the set. The elements of the set will be arranged
in increasing order after this call.
valid_c ( SETSIZ, INISIZ, &dpSet );
Output the elements of the set.
printf( "Set elements:\n" );
for ( i = 0; i < card_c( &dpSet ); i++ )
item = SPICE_CELL_ELEM_D( &dpSet, i );
printf( " %3.1f", item );
printf( "\n" );
return ( 0 );
When this program was executed on a Mac/Intel/cc/64-bit
platform, the output was:
Input data array:
0.0 -1.0 -2.0 -3.0 -4.0 -5.0 -6.0 -7.0 -8.0 -9.0
-9.0 -8.0 -7.0 -6.0 -5.0 -4.0 -3.0 -2.0 -1.0 0.0
1) String comparisons performed by this routine are Fortran-style:
trailing blanks in the input sets are ignored. This gives
consistent behavior with CSPICE code generated by the f2c
translator, as well as with the Fortran SPICE Toolkit.
Note that this behavior is not identical to that of the ANSI
C library functions strcmp and strncmp.
N.J. Bachman (JPL)
C.A. Curzon (JPL)
J. Diaz del Rio (ODC Space)
W.L. Taber (JPL)
I.M. Underwood (JPL)
E.D. Wright (JPL)
-CSPICE Version 1.1.0, 24-NOV-2021 (JDR)
Changed the argument name "set" to "a" for consistency with other
Edited the header to comply with NAIF standard. Extended code example to
generate outputs and inserted example's solution.
Moved misplaced documentation from -Literature_References to
Extended description of argument "a" in -Detailed_Input to include
type and preferred declaration method.
Added entries #2 and #3 in -Exceptions section.
-CSPICE Version 1.0.1, 12-NOV-2006 (EDW)
Corrected minor typo, the -Literature_References header
lacked the prefix "-".
-CSPICE Version 1.0.0, 08-AUG-2002 (NJB) (CAC) (WLT) (IMU)
validate a set