c@427: /* dgemv.f -- translated by f2c (version 20061008).
c@427:    You must link the resulting object file with libf2c:
c@427: 	on Microsoft Windows system, link with libf2c.lib;
c@427: 	on Linux or Unix systems, link with .../path/to/libf2c.a -lm
c@427: 	or, if you install libf2c.a in a standard place, with -lf2c -lm
c@427: 	-- in that order, at the end of the command line, as in
c@427: 		cc *.o -lf2c -lm
c@427: 	Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
c@427: 
c@427: 		http://www.netlib.org/f2c/libf2c.zip
c@427: */
c@427: 
c@427: #include "f2c.h"
c@427: #include "blaswrap.h"
c@427: 
c@427: /* Subroutine */ int dgemv_(char *trans, integer *m, integer *n, doublereal *
c@427: 	alpha, doublereal *a, integer *lda, doublereal *x, integer *incx, 
c@427: 	doublereal *beta, doublereal *y, integer *incy)
c@427: {
c@427:     /* System generated locals */
c@427:     integer a_dim1, a_offset, i__1, i__2;
c@427: 
c@427:     /* Local variables */
c@427:     integer i__, j, ix, iy, jx, jy, kx, ky, info;
c@427:     doublereal temp;
c@427:     integer lenx, leny;
c@427:     extern logical lsame_(char *, char *);
c@427:     extern /* Subroutine */ int xerbla_(char *, integer *);
c@427: 
c@427: /*     .. Scalar Arguments .. */
c@427: /*     .. */
c@427: /*     .. Array Arguments .. */
c@427: /*     .. */
c@427: 
c@427: /*  Purpose */
c@427: /*  ======= */
c@427: 
c@427: /*  DGEMV  performs one of the matrix-vector operations */
c@427: 
c@427: /*     y := alpha*A*x + beta*y,   or   y := alpha*A'*x + beta*y, */
c@427: 
c@427: /*  where alpha and beta are scalars, x and y are vectors and A is an */
c@427: /*  m by n matrix. */
c@427: 
c@427: /*  Arguments */
c@427: /*  ========== */
c@427: 
c@427: /*  TRANS  - CHARACTER*1. */
c@427: /*           On entry, TRANS specifies the operation to be performed as */
c@427: /*           follows: */
c@427: 
c@427: /*              TRANS = 'N' or 'n'   y := alpha*A*x + beta*y. */
c@427: 
c@427: /*              TRANS = 'T' or 't'   y := alpha*A'*x + beta*y. */
c@427: 
c@427: /*              TRANS = 'C' or 'c'   y := alpha*A'*x + beta*y. */
c@427: 
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  M      - INTEGER. */
c@427: /*           On entry, M specifies the number of rows of the matrix A. */
c@427: /*           M must be at least zero. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  N      - INTEGER. */
c@427: /*           On entry, N specifies the number of columns of the matrix A. */
c@427: /*           N must be at least zero. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  ALPHA  - DOUBLE PRECISION. */
c@427: /*           On entry, ALPHA specifies the scalar alpha. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  A      - DOUBLE PRECISION array of DIMENSION ( LDA, n ). */
c@427: /*           Before entry, the leading m by n part of the array A must */
c@427: /*           contain the matrix of coefficients. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  LDA    - INTEGER. */
c@427: /*           On entry, LDA specifies the first dimension of A as declared */
c@427: /*           in the calling (sub) program. LDA must be at least */
c@427: /*           max( 1, m ). */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  X      - DOUBLE PRECISION array of DIMENSION at least */
c@427: /*           ( 1 + ( n - 1 )*abs( INCX ) ) when TRANS = 'N' or 'n' */
c@427: /*           and at least */
c@427: /*           ( 1 + ( m - 1 )*abs( INCX ) ) otherwise. */
c@427: /*           Before entry, the incremented array X must contain the */
c@427: /*           vector x. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  INCX   - INTEGER. */
c@427: /*           On entry, INCX specifies the increment for the elements of */
c@427: /*           X. INCX must not be zero. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  BETA   - DOUBLE PRECISION. */
c@427: /*           On entry, BETA specifies the scalar beta. When BETA is */
c@427: /*           supplied as zero then Y need not be set on input. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: /*  Y      - DOUBLE PRECISION array of DIMENSION at least */
c@427: /*           ( 1 + ( m - 1 )*abs( INCY ) ) when TRANS = 'N' or 'n' */
c@427: /*           and at least */
c@427: /*           ( 1 + ( n - 1 )*abs( INCY ) ) otherwise. */
c@427: /*           Before entry with BETA non-zero, the incremented array Y */
c@427: /*           must contain the vector y. On exit, Y is overwritten by the */
c@427: /*           updated vector y. */
c@427: 
c@427: /*  INCY   - INTEGER. */
c@427: /*           On entry, INCY specifies the increment for the elements of */
c@427: /*           Y. INCY must not be zero. */
c@427: /*           Unchanged on exit. */
c@427: 
c@427: 
c@427: /*  Level 2 Blas routine. */
c@427: 
c@427: /*  -- Written on 22-October-1986. */
c@427: /*     Jack Dongarra, Argonne National Lab. */
c@427: /*     Jeremy Du Croz, Nag Central Office. */
c@427: /*     Sven Hammarling, Nag Central Office. */
c@427: /*     Richard Hanson, Sandia National Labs. */
c@427: 
c@427: 
c@427: /*     .. Parameters .. */
c@427: /*     .. */
c@427: /*     .. Local Scalars .. */
c@427: /*     .. */
c@427: /*     .. External Functions .. */
c@427: /*     .. */
c@427: /*     .. External Subroutines .. */
c@427: /*     .. */
c@427: /*     .. Intrinsic Functions .. */
c@427: /*     .. */
c@427: 
c@427: /*     Test the input parameters. */
c@427: 
c@427:     /* Parameter adjustments */
c@427:     a_dim1 = *lda;
c@427:     a_offset = 1 + a_dim1;
c@427:     a -= a_offset;
c@427:     --x;
c@427:     --y;
c@427: 
c@427:     /* Function Body */
c@427:     info = 0;
c@427:     if (! lsame_(trans, "N") && ! lsame_(trans, "T") && ! lsame_(trans, "C")
c@427: 	    ) {
c@427: 	info = 1;
c@427:     } else if (*m < 0) {
c@427: 	info = 2;
c@427:     } else if (*n < 0) {
c@427: 	info = 3;
c@427:     } else if (*lda < max(1,*m)) {
c@427: 	info = 6;
c@427:     } else if (*incx == 0) {
c@427: 	info = 8;
c@427:     } else if (*incy == 0) {
c@427: 	info = 11;
c@427:     }
c@427:     if (info != 0) {
c@427: 	xerbla_("DGEMV ", &info);
c@427: 	return 0;
c@427:     }
c@427: 
c@427: /*     Quick return if possible. */
c@427: 
c@427:     if (*m == 0 || *n == 0 || *alpha == 0. && *beta == 1.) {
c@427: 	return 0;
c@427:     }
c@427: 
c@427: /*     Set  LENX  and  LENY, the lengths of the vectors x and y, and set */
c@427: /*     up the start points in  X  and  Y. */
c@427: 
c@427:     if (lsame_(trans, "N")) {
c@427: 	lenx = *n;
c@427: 	leny = *m;
c@427:     } else {
c@427: 	lenx = *m;
c@427: 	leny = *n;
c@427:     }
c@427:     if (*incx > 0) {
c@427: 	kx = 1;
c@427:     } else {
c@427: 	kx = 1 - (lenx - 1) * *incx;
c@427:     }
c@427:     if (*incy > 0) {
c@427: 	ky = 1;
c@427:     } else {
c@427: 	ky = 1 - (leny - 1) * *incy;
c@427:     }
c@427: 
c@427: /*     Start the operations. In this version the elements of A are */
c@427: /*     accessed sequentially with one pass through A. */
c@427: 
c@427: /*     First form  y := beta*y. */
c@427: 
c@427:     if (*beta != 1.) {
c@427: 	if (*incy == 1) {
c@427: 	    if (*beta == 0.) {
c@427: 		i__1 = leny;
c@427: 		for (i__ = 1; i__ <= i__1; ++i__) {
c@427: 		    y[i__] = 0.;
c@427: /* L10: */
c@427: 		}
c@427: 	    } else {
c@427: 		i__1 = leny;
c@427: 		for (i__ = 1; i__ <= i__1; ++i__) {
c@427: 		    y[i__] = *beta * y[i__];
c@427: /* L20: */
c@427: 		}
c@427: 	    }
c@427: 	} else {
c@427: 	    iy = ky;
c@427: 	    if (*beta == 0.) {
c@427: 		i__1 = leny;
c@427: 		for (i__ = 1; i__ <= i__1; ++i__) {
c@427: 		    y[iy] = 0.;
c@427: 		    iy += *incy;
c@427: /* L30: */
c@427: 		}
c@427: 	    } else {
c@427: 		i__1 = leny;
c@427: 		for (i__ = 1; i__ <= i__1; ++i__) {
c@427: 		    y[iy] = *beta * y[iy];
c@427: 		    iy += *incy;
c@427: /* L40: */
c@427: 		}
c@427: 	    }
c@427: 	}
c@427:     }
c@427:     if (*alpha == 0.) {
c@427: 	return 0;
c@427:     }
c@427:     if (lsame_(trans, "N")) {
c@427: 
c@427: /*        Form  y := alpha*A*x + y. */
c@427: 
c@427: 	jx = kx;
c@427: 	if (*incy == 1) {
c@427: 	    i__1 = *n;
c@427: 	    for (j = 1; j <= i__1; ++j) {
c@427: 		if (x[jx] != 0.) {
c@427: 		    temp = *alpha * x[jx];
c@427: 		    i__2 = *m;
c@427: 		    for (i__ = 1; i__ <= i__2; ++i__) {
c@427: 			y[i__] += temp * a[i__ + j * a_dim1];
c@427: /* L50: */
c@427: 		    }
c@427: 		}
c@427: 		jx += *incx;
c@427: /* L60: */
c@427: 	    }
c@427: 	} else {
c@427: 	    i__1 = *n;
c@427: 	    for (j = 1; j <= i__1; ++j) {
c@427: 		if (x[jx] != 0.) {
c@427: 		    temp = *alpha * x[jx];
c@427: 		    iy = ky;
c@427: 		    i__2 = *m;
c@427: 		    for (i__ = 1; i__ <= i__2; ++i__) {
c@427: 			y[iy] += temp * a[i__ + j * a_dim1];
c@427: 			iy += *incy;
c@427: /* L70: */
c@427: 		    }
c@427: 		}
c@427: 		jx += *incx;
c@427: /* L80: */
c@427: 	    }
c@427: 	}
c@427:     } else {
c@427: 
c@427: /*        Form  y := alpha*A'*x + y. */
c@427: 
c@427: 	jy = ky;
c@427: 	if (*incx == 1) {
c@427: 	    i__1 = *n;
c@427: 	    for (j = 1; j <= i__1; ++j) {
c@427: 		temp = 0.;
c@427: 		i__2 = *m;
c@427: 		for (i__ = 1; i__ <= i__2; ++i__) {
c@427: 		    temp += a[i__ + j * a_dim1] * x[i__];
c@427: /* L90: */
c@427: 		}
c@427: 		y[jy] += *alpha * temp;
c@427: 		jy += *incy;
c@427: /* L100: */
c@427: 	    }
c@427: 	} else {
c@427: 	    i__1 = *n;
c@427: 	    for (j = 1; j <= i__1; ++j) {
c@427: 		temp = 0.;
c@427: 		ix = kx;
c@427: 		i__2 = *m;
c@427: 		for (i__ = 1; i__ <= i__2; ++i__) {
c@427: 		    temp += a[i__ + j * a_dim1] * x[ix];
c@427: 		    ix += *incx;
c@427: /* L110: */
c@427: 		}
c@427: 		y[jy] += *alpha * temp;
c@427: 		jy += *incy;
c@427: /* L120: */
c@427: 	    }
c@427: 	}
c@427:     }
c@427: 
c@427:     return 0;
c@427: 
c@427: /*     End of DGEMV . */
c@427: 
c@427: } /* dgemv_ */