mirror of https://github.com/opencv/opencv.git
Open Source Computer Vision Library
https://opencv.org/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
232 lines
7.0 KiB
232 lines
7.0 KiB
#include "clapack.h" |
|
#include <assert.h> |
|
|
|
/* Subroutine */ int sgemv_(char *_trans, integer *_m, integer *_n, real *_alpha, |
|
real *a, integer *_lda, real *x, integer *_incx, real *_beta, real *y, |
|
integer *_incy) |
|
{ |
|
|
|
/* .. Scalar Arguments .. */ |
|
/* .. */ |
|
/* .. Array Arguments .. */ |
|
/* .. */ |
|
|
|
/* Purpose */ |
|
/* ======= */ |
|
|
|
/* SGEMV performs one of the matrix-vector operations */ |
|
|
|
/* y := alpha*A*x + beta*y, or y := alpha*A'*x + beta*y, */ |
|
|
|
/* where alpha and beta are scalars, x and y are vectors and A is an */ |
|
/* m by n matrix. */ |
|
|
|
/* Arguments */ |
|
/* ========== */ |
|
|
|
/* TRANS - CHARACTER*1. */ |
|
/* On entry, TRANS specifies the operation to be performed as */ |
|
/* follows: */ |
|
|
|
/* TRANS = 'N' or 'n' y := alpha*A*x + beta*y. */ |
|
|
|
/* TRANS = 'T' or 't' y := alpha*A'*x + beta*y. */ |
|
|
|
/* TRANS = 'C' or 'c' y := alpha*A'*x + beta*y. */ |
|
|
|
/* Unchanged on exit. */ |
|
|
|
/* M - INTEGER. */ |
|
/* On entry, M specifies the number of rows of the matrix A. */ |
|
/* M must be at least zero. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* N - INTEGER. */ |
|
/* On entry, N specifies the number of columns of the matrix A. */ |
|
/* N must be at least zero. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* ALPHA - REAL . */ |
|
/* On entry, ALPHA specifies the scalar alpha. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* A - REAL array of DIMENSION ( LDA, n ). */ |
|
/* Before entry, the leading m by n part of the array A must */ |
|
/* contain the matrix of coefficients. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* LDA - INTEGER. */ |
|
/* On entry, LDA specifies the first dimension of A as declared */ |
|
/* in the calling (sub) program. LDA must be at least */ |
|
/* max( 1, m ). */ |
|
/* Unchanged on exit. */ |
|
|
|
/* X - REAL array of DIMENSION at least */ |
|
/* ( 1 + ( n - 1 )*abs( INCX ) ) when TRANS = 'N' or 'n' */ |
|
/* and at least */ |
|
/* ( 1 + ( m - 1 )*abs( INCX ) ) otherwise. */ |
|
/* Before entry, the incremented array X must contain the */ |
|
/* vector x. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* INCX - INTEGER. */ |
|
/* On entry, INCX specifies the increment for the elements of */ |
|
/* X. INCX must not be zero. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* BETA - REAL . */ |
|
/* On entry, BETA specifies the scalar beta. When BETA is */ |
|
/* supplied as zero then Y need not be set on input. */ |
|
/* Unchanged on exit. */ |
|
|
|
/* Y - REAL array of DIMENSION at least */ |
|
/* ( 1 + ( m - 1 )*abs( INCY ) ) when TRANS = 'N' or 'n' */ |
|
/* and at least */ |
|
/* ( 1 + ( n - 1 )*abs( INCY ) ) otherwise. */ |
|
/* Before entry with BETA non-zero, the incremented array Y */ |
|
/* must contain the vector y. On exit, Y is overwritten by the */ |
|
/* updated vector y. */ |
|
|
|
/* INCY - INTEGER. */ |
|
/* On entry, INCY specifies the increment for the elements of */ |
|
/* Y. INCY must not be zero. */ |
|
/* Unchanged on exit. */ |
|
|
|
|
|
/* Level 2 Blas routine. */ |
|
|
|
/* -- Written on 22-October-1986. */ |
|
/* Jack Dongarra, Argonne National Lab. */ |
|
/* Jeremy Du Croz, Nag Central Office. */ |
|
/* Sven Hammarling, Nag Central Office. */ |
|
/* Richard Hanson, Sandia National Labs. */ |
|
|
|
/* Test the input parameters. */ |
|
|
|
/* Function Body */ |
|
char trans = lapack_toupper(_trans[0]); |
|
integer i, j, m = *_m, n = *_n, lda = *_lda, incx = *_incx, incy = *_incy; |
|
integer leny = trans == 'N' ? m : n, lenx = trans == 'N' ? n : m; |
|
real alpha = *_alpha, beta = *_beta; |
|
|
|
integer info = 0; |
|
if (trans != 'N' && trans != 'T' && trans != 'C') |
|
info = 1; |
|
else if (m < 0) |
|
info = 2; |
|
else if (n < 0) |
|
info = 3; |
|
else if (lda < max(1,m)) |
|
info = 6; |
|
else if (incx == 0) |
|
info = 8; |
|
else if (incy == 0) |
|
info = 11; |
|
|
|
if (info != 0) |
|
{ |
|
xerbla_("SGEMV ", &info); |
|
return 0; |
|
} |
|
|
|
if( incy < 0 ) |
|
y -= incy*(leny - 1); |
|
if( incx < 0 ) |
|
x -= incx*(lenx - 1); |
|
|
|
/* Start the operations. In this version the elements of A are */ |
|
/* accessed sequentially with one pass through A. */ |
|
|
|
if( beta != 1.f ) |
|
{ |
|
if( incy == 1 ) |
|
{ |
|
if( beta == 0.f ) |
|
for( i = 0; i < leny; i++ ) |
|
y[i] = 0.f; |
|
else |
|
for( i = 0; i < leny; i++ ) |
|
y[i] *= beta; |
|
} |
|
else |
|
{ |
|
if( beta == 0.f ) |
|
for( i = 0; i < leny; i++ ) |
|
y[i*incy] = 0.f; |
|
else |
|
for( i = 0; i < leny; i++ ) |
|
y[i*incy] *= beta; |
|
} |
|
} |
|
|
|
if( alpha == 0.f ) |
|
; |
|
else if( trans == 'N' ) |
|
{ |
|
if( incy == 1 ) |
|
{ |
|
for( i = 0; i < n; i++, a += lda ) |
|
{ |
|
real s = x[i*incx]; |
|
if( s == 0.f ) |
|
continue; |
|
s *= alpha; |
|
|
|
for( j = 0; j <= m - 4; j += 4 ) |
|
{ |
|
real t0 = y[j] + s*a[j]; |
|
real t1 = y[j+1] + s*a[j+1]; |
|
y[j] = t0; y[j+1] = t1; |
|
t0 = y[j+2] + s*a[j+2]; |
|
t1 = y[j+3] + s*a[j+3]; |
|
y[j+2] = t0; y[j+3] = t1; |
|
} |
|
|
|
for( ; j < m; j++ ) |
|
y[j] += s*a[j]; |
|
} |
|
} |
|
else |
|
{ |
|
for( i = 0; i < n; i++, a += lda ) |
|
{ |
|
real s = x[i*incx]; |
|
if( s == 0. ) |
|
continue; |
|
s *= alpha; |
|
for( j = 0; j < m; j++ ) |
|
y[j*incy] += s*a[j]; |
|
} |
|
} |
|
} |
|
else |
|
{ |
|
if( incx == 1 ) |
|
{ |
|
for( i = 0; i < n; i++, a += lda ) |
|
{ |
|
real s = 0; |
|
for( j = 0; j <= m - 4; j += 4 ) |
|
s += x[j]*a[j] + x[j+1]*a[j+1] + x[j+2]*a[j+2] + x[j+3]*a[j+3]; |
|
for( ; j < m; j++ ) |
|
s += x[j]*a[j]; |
|
y[i*incy] += alpha*s; |
|
} |
|
} |
|
else |
|
{ |
|
for( i = 0; i < n; i++, a += lda ) |
|
{ |
|
real s = 0; |
|
for( j = 0; j < m; j++ ) |
|
s += x[j*incx]*a[j]; |
|
y[i*incy] += alpha*s; |
|
} |
|
} |
|
} |
|
|
|
return 0; |
|
|
|
/* End of SGEMV . */ |
|
|
|
} /* sgemv_ */
|
|
|