alibGetTrace
Retrieves a general subset of an array. Unlike
alibGetRange and
alibGetSubset, the subset need not be a subarray, e.g., the main diagonal of an array. If the subset is a subarray it is more efficiently retrieved with the other routines. The PV-WAVE API for this routine is
Array Subscripting where all subscripts are arrays of the same length.
Prototypes
void alibGetTraceb( wvlong n, wvlong *d, wvlong b, wvlong **e, UCHAR *p, UCHAR *q )
void alibGetTraces( wvlong n, wvlong *d, wvlong b, wvlong **e, short *p, short *q )
void alibGetTracei( wvlong n, wvlong *d, wvlong b, wvlong **e, int *p, int *q )
void alibGetTracel( wvlong n, wvlong *d, wvlong b, wvlong **e, wvlong *p, wvlong *q )
void alibGetTracef( wvlong n, wvlong *d, wvlong b, wvlong **e, float *p, float *q )
void alibGetTraced( wvlong n, wvlong *d, wvlong b, wvlong **e, double *p, double *q )
void alibGetTracec( wvlong n, wvlong *d, wvlong b, wvlong **e, COMPLEX *p, COMPLEX *q )
void alibGetTracez( wvlong n, wvlong *d, wvlong b, wvlong **e, DCOMPLEX *p, DCOMPLEX *q )
Parameters
n — (Input) The number of dimensions in the source array.
*d — (Input) The n-element array of dimensions in the source array.
b — (Input) The number of elements in each of n index arrays.
**e — (Input) The n-element array of pointers to b-element index arrays. The n b-element index arrays e define b points in the n-dimensional source array.
*p — (Input) The source array.
*q — (Input/Output) The destination array. On return, array q is a copy of the data at the b points e in array p.
Example
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "alib.h"
void main() { /* array of dimensions to use for one-dimensional, */
/* two-dimensional, three-dimensional, and */
/* four-dimensional examples */
wvlong dsrc[4] = {2,3,3,3}; /* index arrays to use for one-dimensional, */
/* two-dimensional, three-dimensional, and */
/* four-dimensional examples */
wvlong ind0[2] = {0,2}; wvlong ind1[6] = {0,1,2,0,1,2}; wvlong ind2[6] = {0,0,0,1,1,1}; wvlong *indx[5] = {ind2,ind1,ind1,ind1,ind0}; /* output array big enough for one-dimensional, */
/* two-dimensional, three-dimensional, and */
/* four-dimensional examples */
UCHAR b[6];
/* fabricate enough test data for one-dimensional, */
/* two-dimensional, three-dimensional, and */
/* four-dimensional examples */
UCHAR *b0;
b0 = (UCHAR*)malloc(54*sizeof(UCHAR));
alibinit( NULL, NULL, NULL, NULL );
alibIndexb( 54, 0, 1, b0 );
printf( "\n\n print 1d-array, retrieve and print its even-indexed data" );
alibPrintArrayb( 1, 1, 1, 3, b0, NULL );
alibGetTraceb( 1, &dsrc[3], 2, &indx[4], b0, b );
alibPrintArrayb( 1, 1, 1, 2, b, NULL );
printf( "\n\n print 2d-array, retrieve and print its main diagonal" );
alibPrintArrayb( 1, 1, 3, 3, b0, NULL );
alibGetTraceb( 2, &dsrc[2], 3, &indx[2], b0, b );
alibPrintArrayb( 1, 1, 1, 3, b, NULL );
printf( "\n\n print 3d-array, retrieve and print its main diagonal" );
alibPrintArrayb( 1, 3, 3, 3, b0, NULL );
alibGetTraceb( 3, &dsrc[1], 3, &indx[1], b0, b );
alibPrintArrayb( 1, 1, 1, 3, b, NULL );
printf( "\n\n print 4d-array with leading dimension of 2, retrieve \n" );
printf( " and print main diagonal from each three-dimensional slice of that dimension");
alibPrintArrayb( 2, 3, 3, 3, b0, NULL );
alibGetTraceb( 4, dsrc, 6, indx, b0, b );
alibPrintArrayb( 1, 1, 2, 3, b, NULL );
}
Output:
print 1d-array, retrieve and print its even-indexed data
0 1 2
0 2
print 2d-array, retrieve and print its main diagonal
0 1 2
3 4 5
6 7 8
0 4 8
print 3d-array, retrieve and print its main diagonal
0 1 2
3 4 5
6 7 8
9 10 11
12 13 14
15 16 17
18 19 20
21 22 23
24 25 26
0 13 26
print 4d-array with leading dimension of 2, retrieve
and print main diagonal from each three-dimensional slice of that dimension
0 1 2
3 4 5
6 7 8
9 10 11
12 13 14
15 16 17
18 19 20
21 22 23
24 25 26
27 28 29
30 31 32
33 34 35
36 37 38
39 40 41
42 43 44
45 46 47
48 49 50
51 52 53
0 13 26
27 40 53
Version 2017.1
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