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.
144 lines
4.2 KiB
144 lines
4.2 KiB
#include "blaswrap.h"
|
|
#include "f2c.h"
|
|
|
|
/* Subroutine */ int dger_(integer *m, integer *n, doublereal *alpha,
|
|
doublereal *x, integer *incx, doublereal *y, integer *incy,
|
|
doublereal *a, integer *lda)
|
|
{
|
|
/* System generated locals */
|
|
integer a_dim1, a_offset, i__1, i__2;
|
|
/* Local variables */
|
|
static integer info;
|
|
static doublereal temp;
|
|
static integer i__, j, ix, jy, kx;
|
|
extern /* Subroutine */ int xerbla_(char *, integer *);
|
|
#define a_ref(a_1,a_2) a[(a_2)*a_dim1 + a_1]
|
|
/* Purpose
|
|
=======
|
|
DGER performs the rank 1 operation
|
|
A := alpha*x*y' + A,
|
|
where alpha is a scalar, x is an m element vector, y is an n element
|
|
vector and A is an m by n matrix.
|
|
Parameters
|
|
==========
|
|
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 - DOUBLE PRECISION.
|
|
On entry, ALPHA specifies the scalar alpha.
|
|
Unchanged on exit.
|
|
X - DOUBLE PRECISION array of dimension at least
|
|
( 1 + ( m - 1 )*abs( INCX ) ).
|
|
Before entry, the incremented array X must contain the m
|
|
element 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.
|
|
Y - DOUBLE PRECISION array of dimension at least
|
|
( 1 + ( n - 1 )*abs( INCY ) ).
|
|
Before entry, the incremented array Y must contain the n
|
|
element vector y.
|
|
Unchanged on exit.
|
|
INCY - INTEGER.
|
|
On entry, INCY specifies the increment for the elements of
|
|
Y. INCY must not be zero.
|
|
Unchanged on exit.
|
|
A - DOUBLE PRECISION array of DIMENSION ( LDA, n ).
|
|
Before entry, the leading m by n part of the array A must
|
|
contain the matrix of coefficients. On exit, A is
|
|
overwritten by the updated matrix.
|
|
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.
|
|
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.
|
|
Parameter adjustments */
|
|
--x;
|
|
--y;
|
|
a_dim1 = *lda;
|
|
a_offset = 1 + a_dim1 * 1;
|
|
a -= a_offset;
|
|
/* Function Body */
|
|
info = 0;
|
|
if (*m < 0) {
|
|
info = 1;
|
|
} else if (*n < 0) {
|
|
info = 2;
|
|
} else if (*incx == 0) {
|
|
info = 5;
|
|
} else if (*incy == 0) {
|
|
info = 7;
|
|
} else if (*lda < max(1,*m)) {
|
|
info = 9;
|
|
}
|
|
if (info != 0) {
|
|
xerbla_("DGER ", &info);
|
|
return 0;
|
|
}
|
|
/* Quick return if possible. */
|
|
if (*m == 0 || *n == 0 || *alpha == 0.) {
|
|
return 0;
|
|
}
|
|
/* Start the operations. In this version the elements of A are
|
|
accessed sequentially with one pass through A. */
|
|
if (*incy > 0) {
|
|
jy = 1;
|
|
} else {
|
|
jy = 1 - (*n - 1) * *incy;
|
|
}
|
|
if (*incx == 1) {
|
|
i__1 = *n;
|
|
for (j = 1; j <= i__1; ++j) {
|
|
if (y[jy] != 0.) {
|
|
temp = *alpha * y[jy];
|
|
i__2 = *m;
|
|
for (i__ = 1; i__ <= i__2; ++i__) {
|
|
a_ref(i__, j) = a_ref(i__, j) + x[i__] * temp;
|
|
/* L10: */
|
|
}
|
|
}
|
|
jy += *incy;
|
|
/* L20: */
|
|
}
|
|
} else {
|
|
if (*incx > 0) {
|
|
kx = 1;
|
|
} else {
|
|
kx = 1 - (*m - 1) * *incx;
|
|
}
|
|
i__1 = *n;
|
|
for (j = 1; j <= i__1; ++j) {
|
|
if (y[jy] != 0.) {
|
|
temp = *alpha * y[jy];
|
|
ix = kx;
|
|
i__2 = *m;
|
|
for (i__ = 1; i__ <= i__2; ++i__) {
|
|
a_ref(i__, j) = a_ref(i__, j) + x[ix] * temp;
|
|
ix += *incx;
|
|
/* L30: */
|
|
}
|
|
}
|
|
jy += *incy;
|
|
/* L40: */
|
|
}
|
|
}
|
|
return 0;
|
|
/* End of DGER . */
|
|
} /* dger_ */
|
|
#undef a_ref
|
|
|