RWalib C Array Library User Guide > Arithmetic Operations > alibSumDim
  

alibSumDim
Sums the elements along one dimension of an array. The PV-WAVE API for this routine is the TOTAL Function with Dimension keyword.
Prototypes
void alibSumDimb( wvlong m, wvlong n, wvlong *d, UCHAR *p, float *q )
void alibSumDims( wvlong m, wvlong n, wvlong *d, short *p, float *q )
void alibSumDimi( wvlong m, wvlong n, wvlong *d, int *p, float *q )
void alibSumDiml( wvlong m, wvlong n, wvlong *d, wvlong *p, float *q )
void alibSumDimf( wvlong m, wvlong n, wvlong *d, float *p, float *q )
void alibSumDimd( wvlong m, wvlong n, wvlong *d, double *p, double *q )
void alibSumDimc( wvlong m, wvlong n, wvlong *d, COMPLEX *p, COMPLEX *q )
void alibSumDimz( wvlong m, wvlong n, wvlong *d, DCOMPLEX *p, DCOMPLEX *q )
Parameters
m — (Input) The dimension (>=0) along which elements are summed. In a matrix for example, set m=0 to sum each column or set m=1 to sum each row.
n — (Input) The number of dimensions in the source array.
*d — (Input) The n-element array of dimensions for the source array.
*p — (Input) The n-dimensional source array of dimensions d.
*q — (Input/Output) The destination array. On output, array q contains the sum of each 'column' along dimension m, and it is usually interpreted as (n–1)-dimensional with dimensions d[0], ..., d[m–1], 1, d[m+1], ..., d[n–1]. Computation is done in the data-type of array q.
Example
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "alib.h"
void main() {
    /* arrays of dimensions to use for all the examples */
        wvlong dm[4]={4,3,2,2};
    /* source data for all the examples */
        UCHAR b0[48];
    /* output array to use for all the examples */
        float b[24];
    /* initialize the source data */
        alibinit( NULL, NULL, NULL, NULL );
        alibIndexb( 48, 0, 1, b0 );
    printf( "\n\n show a (4,3) matrix" );
        alibPrintArrayb( 1, 1, 4, 3, b0, NULL );
    printf( "\n\n sum over dimension 0, i.e. sum each column" );
        alibSumDimb( 0, 2, dm, b0, b );
        alibPrintArrayf( 1, 1, 1, 3, b, NULL );
    printf( "\n\n sum over dimension 1, i.e. sum each row" );
        alibSumDimb( 1, 2, dm, b0, b );
        alibPrintArrayf( 1, 1, 4, 1, b, NULL );
    printf( "\n\n show a (4,3,2) array" );
        alibPrintArrayb( 1, 4, 3, 2, b0, NULL );
    printf( "\n\n sum over dimension 0" );
        alibSumDimb( 0, 3, dm, b0, b );
        alibPrintArrayf( 1, 1, 3, 2, b, NULL );
    printf( "\n\n sum over dimension 1" );
        alibSumDimb( 1, 3, dm, b0, b );
        alibPrintArrayf( 1, 4, 1, 2, b, NULL );
    printf( "\n\n sum over dimension 2" );
        alibSumDimb( 2, 3, dm, b0, b );
        alibPrintArrayf( 1, 4, 3, 1, b, NULL );
    printf( "\n\n show a (4,3,2,2) array" );
        alibPrintArrayb( 4, 3, 2, 2, b0, NULL );
    printf( "\n\n sum over dimension 0" );
        alibSumDimb( 0, 4, dm, b0, b );
        alibPrintArrayf( 1, 3, 2, 2, b, NULL );
}
 
Output:
 
 show a (4,3) matrix
 
   0   1   2
   3   4   5
   6   7   8
   9  10  11
 
 sum over dimension 0, i.e. sum each column
 
   1.800e+01   2.200e+01   2.600e+01
 
 sum over dimension 1, i.e. sum each row
 
   3.000e+00
   1.200e+01
   2.100e+01
   3.000e+01
 
 show a (4,3,2) array
 
   0   1
   2   3
   4   5
 
   6   7
   8   9
  10  11
 
  12  13
  14  15
  16  17
 
  18  19
  20  21
  22  23
 
 sum over dimension 0
 
   3.600e+01   4.000e+01
   4.400e+01   4.800e+01
   5.200e+01   5.600e+01
 
 sum over dimension 1
 
   6.000e+00   9.000e+00
 
   2.400e+01   2.700e+01
 
   4.200e+01   4.500e+01
 
   6.000e+01   6.300e+01
 
 sum over dimension 2
 
   1.000e+00
   5.000e+00
   9.000e+00
 
   1.300e+01
   1.700e+01
   2.100e+01
 
   2.500e+01
   2.900e+01
   3.300e+01
 
   3.700e+01
   4.100e+01
   4.500e+01
 
 show a (4,3,2,2) array
 
   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
 
 sum over dimension 0
 
   7.200e+01   7.600e+01
   8.000e+01   8.400e+01
 
   8.800e+01   9.200e+01
   9.600e+01   1.000e+02
 
   1.040e+02   1.080e+02
   1.120e+02   1.160e+02

Version 2017.0
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