LAPACK  3.6.1 LAPACK: Linear Algebra PACKage
cblas_example1.c
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1 /* cblas_example.c */
2
3 #include <stdio.h>
4 #include <stdlib.h>
5 #include "cblas.h"
6
7 int main ( )
8 {
9  CBLAS_LAYOUT Layout;
10  CBLAS_TRANSPOSE transa;
11
12  double *a, *x, *y;
13  double alpha, beta;
14  int m, n, lda, incx, incy, i;
15
16  Layout = CblasColMajor;
17  transa = CblasNoTrans;
18
19  m = 4; /* Size of Column ( the number of rows ) */
20  n = 4; /* Size of Row ( the number of columns ) */
21  lda = 4; /* Leading dimension of 5 * 4 matrix is 5 */
22  incx = 1;
23  incy = 1;
24  alpha = 1;
25  beta = 0;
26
27  a = (double *)malloc(sizeof(double)*m*n);
28  x = (double *)malloc(sizeof(double)*n);
29  y = (double *)malloc(sizeof(double)*n);
30  /* The elements of the first column */
31  a[0] = 1;
32  a[1] = 2;
33  a[2] = 3;
34  a[3] = 4;
35  /* The elements of the second column */
36  a[m] = 1;
37  a[m+1] = 1;
38  a[m+2] = 1;
39  a[m+3] = 1;
40  /* The elements of the third column */
41  a[m*2] = 3;
42  a[m*2+1] = 4;
43  a[m*2+2] = 5;
44  a[m*2+3] = 6;
45  /* The elements of the fourth column */
46  a[m*3] = 5;
47  a[m*3+1] = 6;
48  a[m*3+2] = 7;
49  a[m*3+3] = 8;
50  /* The elemetns of x and y */
51  x[0] = 1;
52  x[1] = 2;
53  x[2] = 1;
54  x[3] = 1;
55  y[0] = 0;
56  y[1] = 0;
57  y[2] = 0;
58  y[3] = 0;
59
60  cblas_dgemv( Layout, transa, m, n, alpha, a, lda, x, incx, beta,
61  y, incy );
62  /* Print y */
63  for( i = 0; i < n; i++ )
64  printf(" y%d = %f\n", i, y[i]);
65  free(a);
66  free(x);
67  free(y);
68  return 0;
69 }
CBLAS_TRANSPOSE
Definition: cblas.h:20
void cblas_dgemv(CBLAS_LAYOUT layout, CBLAS_TRANSPOSE TransA, const int M, const int N, const double alpha, const double *A, const int lda, const double *X, const int incX, const double beta, double *Y, const int incY)
Definition: cblas_dgemv.c:11
int main()
Definition: cblas_example1.c:7
CBLAS_LAYOUT
Definition: cblas.h:19