convert linalg library from Fortran to C++
This commit is contained in:
Axel Kohlmeyer
385
lib/linalg/dgemv.cpp
Normal file
385
lib/linalg/dgemv.cpp
Normal file
@ -0,0 +1,385 @@
|
||||
/* fortran/dgemv.f -- translated by f2c (version 20200916).
|
||||
You must link the resulting object file with libf2c:
|
||||
on Microsoft Windows system, link with libf2c.lib;
|
||||
on Linux or Unix systems, link with .../path/to/libf2c.a -lm
|
||||
or, if you install libf2c.a in a standard place, with -lf2c -lm
|
||||
-- in that order, at the end of the command line, as in
|
||||
cc *.o -lf2c -lm
|
||||
Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
|
||||
|
||||
http://www.netlib.org/f2c/libf2c.zip
|
||||
*/
|
||||
|
||||
#ifdef __cplusplus
|
||||
extern "C" {
|
||||
#endif
|
||||
#include "lmp_f2c.h"
|
||||
|
||||
/* > \brief \b DGEMV */
|
||||
|
||||
/* =========== DOCUMENTATION =========== */
|
||||
|
||||
/* Online html documentation available at */
|
||||
/* http://www.netlib.org/lapack/explore-html/ */
|
||||
|
||||
/* Definition: */
|
||||
/* =========== */
|
||||
|
||||
/* SUBROUTINE DGEMV(TRANS,M,N,ALPHA,A,LDA,X,INCX,BETA,Y,INCY) */
|
||||
|
||||
/* .. Scalar Arguments .. */
|
||||
/* DOUBLE PRECISION ALPHA,BETA */
|
||||
/* INTEGER INCX,INCY,LDA,M,N */
|
||||
/* CHARACTER TRANS */
|
||||
/* .. */
|
||||
/* .. Array Arguments .. */
|
||||
/* DOUBLE PRECISION A(LDA,*),X(*),Y(*) */
|
||||
/* .. */
|
||||
|
||||
|
||||
/* > \par Purpose: */
|
||||
/* ============= */
|
||||
/* > */
|
||||
/* > \verbatim */
|
||||
/* > */
|
||||
/* > DGEMV performs one of the matrix-vector operations */
|
||||
/* > */
|
||||
/* > y := alpha*A*x + beta*y, or y := alpha*A**T*x + beta*y, */
|
||||
/* > */
|
||||
/* > where alpha and beta are scalars, x and y are vectors and A is an */
|
||||
/* > m by n matrix. */
|
||||
/* > \endverbatim */
|
||||
|
||||
/* Arguments: */
|
||||
/* ========== */
|
||||
|
||||
/* > \param[in] TRANS */
|
||||
/* > \verbatim */
|
||||
/* > TRANS is 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**T*x + beta*y. */
|
||||
/* > */
|
||||
/* > TRANS = 'C' or 'c' y := alpha*A**T*x + beta*y. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] M */
|
||||
/* > \verbatim */
|
||||
/* > M is INTEGER */
|
||||
/* > On entry, M specifies the number of rows of the matrix A. */
|
||||
/* > M must be at least zero. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] N */
|
||||
/* > \verbatim */
|
||||
/* > N is INTEGER */
|
||||
/* > On entry, N specifies the number of columns of the matrix A. */
|
||||
/* > N must be at least zero. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] ALPHA */
|
||||
/* > \verbatim */
|
||||
/* > ALPHA is DOUBLE PRECISION. */
|
||||
/* > On entry, ALPHA specifies the scalar alpha. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] A */
|
||||
/* > \verbatim */
|
||||
/* > A is DOUBLE PRECISION array, dimension ( LDA, N ) */
|
||||
/* > Before entry, the leading m by n part of the array A must */
|
||||
/* > contain the matrix of coefficients. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] LDA */
|
||||
/* > \verbatim */
|
||||
/* > LDA is 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 ). */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] X */
|
||||
/* > \verbatim */
|
||||
/* > X is DOUBLE PRECISION array, 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. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] INCX */
|
||||
/* > \verbatim */
|
||||
/* > INCX is INTEGER */
|
||||
/* > On entry, INCX specifies the increment for the elements of */
|
||||
/* > X. INCX must not be zero. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] BETA */
|
||||
/* > \verbatim */
|
||||
/* > BETA is DOUBLE PRECISION. */
|
||||
/* > On entry, BETA specifies the scalar beta. When BETA is */
|
||||
/* > supplied as zero then Y need not be set on input. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in,out] Y */
|
||||
/* > \verbatim */
|
||||
/* > Y is DOUBLE PRECISION array, 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. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* > \param[in] INCY */
|
||||
/* > \verbatim */
|
||||
/* > INCY is INTEGER */
|
||||
/* > On entry, INCY specifies the increment for the elements of */
|
||||
/* > Y. INCY must not be zero. */
|
||||
/* > \endverbatim */
|
||||
|
||||
/* Authors: */
|
||||
/* ======== */
|
||||
|
||||
/* > \author Univ. of Tennessee */
|
||||
/* > \author Univ. of California Berkeley */
|
||||
/* > \author Univ. of Colorado Denver */
|
||||
/* > \author NAG Ltd. */
|
||||
|
||||
/* > \ingroup double_blas_level2 */
|
||||
|
||||
/* > \par Further Details: */
|
||||
/* ===================== */
|
||||
/* > */
|
||||
/* > \verbatim */
|
||||
/* > */
|
||||
/* > Level 2 Blas routine. */
|
||||
/* > The vector and matrix arguments are not referenced when N = 0, or M = 0 */
|
||||
/* > */
|
||||
/* > -- 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. */
|
||||
/* > \endverbatim */
|
||||
/* > */
|
||||
/* ===================================================================== */
|
||||
/* Subroutine */ int dgemv_(char *trans, integer *m, integer *n, doublereal *
|
||||
alpha, doublereal *a, integer *lda, doublereal *x, integer *incx,
|
||||
doublereal *beta, doublereal *y, integer *incy, ftnlen trans_len)
|
||||
{
|
||||
/* System generated locals */
|
||||
integer a_dim1, a_offset, i__1, i__2;
|
||||
|
||||
/* Local variables */
|
||||
integer i__, j, ix, iy, jx, jy, kx, ky, info;
|
||||
doublereal temp;
|
||||
integer lenx, leny;
|
||||
extern logical lsame_(char *, char *, ftnlen, ftnlen);
|
||||
extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
|
||||
|
||||
|
||||
/* -- Reference BLAS level2 routine -- */
|
||||
/* -- Reference BLAS is a software package provided by Univ. of Tennessee, -- */
|
||||
/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
|
||||
|
||||
/* .. Scalar Arguments .. */
|
||||
/* .. */
|
||||
/* .. Array Arguments .. */
|
||||
/* .. */
|
||||
|
||||
/* ===================================================================== */
|
||||
|
||||
/* .. Parameters .. */
|
||||
/* .. */
|
||||
/* .. Local Scalars .. */
|
||||
/* .. */
|
||||
/* .. External Functions .. */
|
||||
/* .. */
|
||||
/* .. External Subroutines .. */
|
||||
/* .. */
|
||||
/* .. Intrinsic Functions .. */
|
||||
/* .. */
|
||||
|
||||
/* Test the input parameters. */
|
||||
|
||||
/* Parameter adjustments */
|
||||
a_dim1 = *lda;
|
||||
a_offset = 1 + a_dim1;
|
||||
a -= a_offset;
|
||||
--x;
|
||||
--y;
|
||||
|
||||
/* Function Body */
|
||||
info = 0;
|
||||
if (! lsame_(trans, (char *)"N", (ftnlen)1, (ftnlen)1) && ! lsame_(trans, (char *)"T", (
|
||||
ftnlen)1, (ftnlen)1) && ! lsame_(trans, (char *)"C", (ftnlen)1, (ftnlen)1)
|
||||
) {
|
||||
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_((char *)"DGEMV ", &info, (ftnlen)6);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Quick return if possible. */
|
||||
|
||||
if (*m == 0 || *n == 0 || *alpha == 0. && *beta == 1.) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Set LENX and LENY, the lengths of the vectors x and y, and set */
|
||||
/* up the start points in X and Y. */
|
||||
|
||||
if (lsame_(trans, (char *)"N", (ftnlen)1, (ftnlen)1)) {
|
||||
lenx = *n;
|
||||
leny = *m;
|
||||
} else {
|
||||
lenx = *m;
|
||||
leny = *n;
|
||||
}
|
||||
if (*incx > 0) {
|
||||
kx = 1;
|
||||
} else {
|
||||
kx = 1 - (lenx - 1) * *incx;
|
||||
}
|
||||
if (*incy > 0) {
|
||||
ky = 1;
|
||||
} else {
|
||||
ky = 1 - (leny - 1) * *incy;
|
||||
}
|
||||
|
||||
/* Start the operations. In this version the elements of A are */
|
||||
/* accessed sequentially with one pass through A. */
|
||||
|
||||
/* First form y := beta*y. */
|
||||
|
||||
if (*beta != 1.) {
|
||||
if (*incy == 1) {
|
||||
if (*beta == 0.) {
|
||||
i__1 = leny;
|
||||
for (i__ = 1; i__ <= i__1; ++i__) {
|
||||
y[i__] = 0.;
|
||||
/* L10: */
|
||||
}
|
||||
} else {
|
||||
i__1 = leny;
|
||||
for (i__ = 1; i__ <= i__1; ++i__) {
|
||||
y[i__] = *beta * y[i__];
|
||||
/* L20: */
|
||||
}
|
||||
}
|
||||
} else {
|
||||
iy = ky;
|
||||
if (*beta == 0.) {
|
||||
i__1 = leny;
|
||||
for (i__ = 1; i__ <= i__1; ++i__) {
|
||||
y[iy] = 0.;
|
||||
iy += *incy;
|
||||
/* L30: */
|
||||
}
|
||||
} else {
|
||||
i__1 = leny;
|
||||
for (i__ = 1; i__ <= i__1; ++i__) {
|
||||
y[iy] = *beta * y[iy];
|
||||
iy += *incy;
|
||||
/* L40: */
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
if (*alpha == 0.) {
|
||||
return 0;
|
||||
}
|
||||
if (lsame_(trans, (char *)"N", (ftnlen)1, (ftnlen)1)) {
|
||||
|
||||
/* Form y := alpha*A*x + y. */
|
||||
|
||||
jx = kx;
|
||||
if (*incy == 1) {
|
||||
i__1 = *n;
|
||||
for (j = 1; j <= i__1; ++j) {
|
||||
temp = *alpha * x[jx];
|
||||
i__2 = *m;
|
||||
for (i__ = 1; i__ <= i__2; ++i__) {
|
||||
y[i__] += temp * a[i__ + j * a_dim1];
|
||||
/* L50: */
|
||||
}
|
||||
jx += *incx;
|
||||
/* L60: */
|
||||
}
|
||||
} else {
|
||||
i__1 = *n;
|
||||
for (j = 1; j <= i__1; ++j) {
|
||||
temp = *alpha * x[jx];
|
||||
iy = ky;
|
||||
i__2 = *m;
|
||||
for (i__ = 1; i__ <= i__2; ++i__) {
|
||||
y[iy] += temp * a[i__ + j * a_dim1];
|
||||
iy += *incy;
|
||||
/* L70: */
|
||||
}
|
||||
jx += *incx;
|
||||
/* L80: */
|
||||
}
|
||||
}
|
||||
} else {
|
||||
|
||||
/* Form y := alpha*A**T*x + y. */
|
||||
|
||||
jy = ky;
|
||||
if (*incx == 1) {
|
||||
i__1 = *n;
|
||||
for (j = 1; j <= i__1; ++j) {
|
||||
temp = 0.;
|
||||
i__2 = *m;
|
||||
for (i__ = 1; i__ <= i__2; ++i__) {
|
||||
temp += a[i__ + j * a_dim1] * x[i__];
|
||||
/* L90: */
|
||||
}
|
||||
y[jy] += *alpha * temp;
|
||||
jy += *incy;
|
||||
/* L100: */
|
||||
}
|
||||
} else {
|
||||
i__1 = *n;
|
||||
for (j = 1; j <= i__1; ++j) {
|
||||
temp = 0.;
|
||||
ix = kx;
|
||||
i__2 = *m;
|
||||
for (i__ = 1; i__ <= i__2; ++i__) {
|
||||
temp += a[i__ + j * a_dim1] * x[ix];
|
||||
ix += *incx;
|
||||
/* L110: */
|
||||
}
|
||||
y[jy] += *alpha * temp;
|
||||
jy += *incy;
|
||||
/* L120: */
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return 0;
|
||||
|
||||
/* End of DGEMV */
|
||||
|
||||
} /* dgemv_ */
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
#endif
|
||||
Reference in New Issue
Block a user