zlaset.c

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/* zlaset.f -- translated by f2c (version 20061008).
   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
*/

#include "f2c.h"
#include "blaswrap.h"

/* Subroutine */ int zlaset_(char *uplo, integer *m, integer *n, 
        doublecomplex *alpha, doublecomplex *beta, doublecomplex *a, integer *
        lda)
{
    /* System generated locals */
    integer a_dim1, a_offset, i__1, i__2, i__3;

    /* Local variables */
    integer i__, j;
    extern logical lsame_(char *, char *);


/*  -- LAPACK auxiliary routine (version 3.2) -- */
/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/*     November 2006 */

/*     .. Scalar Arguments .. */
/*     .. */
/*     .. Array Arguments .. */
/*     .. */

/*  Purpose */
/*  ======= */

/*  ZLASET initializes a 2-D array A to BETA on the diagonal and */
/*  ALPHA on the offdiagonals. */

/*  Arguments */
/*  ========= */

/*  UPLO    (input) CHARACTER*1 */
/*          Specifies the part of the matrix A to be set. */
/*          = 'U':      Upper triangular part is set. The lower triangle */
/*                      is unchanged. */
/*          = 'L':      Lower triangular part is set. The upper triangle */
/*                      is unchanged. */
/*          Otherwise:  All of the matrix A is set. */

/*  M       (input) INTEGER */
/*          On entry, M specifies the number of rows of A. */

/*  N       (input) INTEGER */
/*          On entry, N specifies the number of columns of A. */

/*  ALPHA   (input) COMPLEX*16 */
/*          All the offdiagonal array elements are set to ALPHA. */

/*  BETA    (input) COMPLEX*16 */
/*          All the diagonal array elements are set to BETA. */

/*  A       (input/output) COMPLEX*16 array, dimension (LDA,N) */
/*          On entry, the m by n matrix A. */
/*          On exit, A(i,j) = ALPHA, 1 <= i <= m, 1 <= j <= n, i.ne.j; */
/*                   A(i,i) = BETA , 1 <= i <= min(m,n) */

/*  LDA     (input) INTEGER */
/*          The leading dimension of the array A.  LDA >= max(1,M). */

/*  ===================================================================== */

/*     .. Local Scalars .. */
/*     .. */
/*     .. External Functions .. */
/*     .. */
/*     .. Intrinsic Functions .. */
/*     .. */
/*     .. Executable Statements .. */

    /* Parameter adjustments */
    a_dim1 = *lda;
    a_offset = 1 + a_dim1;
    a -= a_offset;

    /* Function Body */
    if (lsame_(uplo, "U")) {

/*        Set the diagonal to BETA and the strictly upper triangular */
/*        part of the array to ALPHA. */

        i__1 = *n;
        for (j = 2; j <= i__1; ++j) {
/* Computing MIN */
            i__3 = j - 1;
            i__2 = min(i__3,*m);
            for (i__ = 1; i__ <= i__2; ++i__) {
                i__3 = i__ + j * a_dim1;
                a[i__3].r = alpha->r, a[i__3].i = alpha->i;
/* L10: */
            }
/* L20: */
        }
        i__1 = min(*n,*m);
        for (i__ = 1; i__ <= i__1; ++i__) {
            i__2 = i__ + i__ * a_dim1;
            a[i__2].r = beta->r, a[i__2].i = beta->i;
/* L30: */
        }

    } else if (lsame_(uplo, "L")) {

/*        Set the diagonal to BETA and the strictly lower triangular */
/*        part of the array to ALPHA. */

        i__1 = min(*m,*n);
        for (j = 1; j <= i__1; ++j) {
            i__2 = *m;
            for (i__ = j + 1; i__ <= i__2; ++i__) {
                i__3 = i__ + j * a_dim1;
                a[i__3].r = alpha->r, a[i__3].i = alpha->i;
/* L40: */
            }
/* L50: */
        }
        i__1 = min(*n,*m);
        for (i__ = 1; i__ <= i__1; ++i__) {
            i__2 = i__ + i__ * a_dim1;
            a[i__2].r = beta->r, a[i__2].i = beta->i;
/* L60: */
        }

    } else {

/*        Set the array to BETA on the diagonal and ALPHA on the */
/*        offdiagonal. */

        i__1 = *n;
        for (j = 1; j <= i__1; ++j) {
            i__2 = *m;
            for (i__ = 1; i__ <= i__2; ++i__) {
                i__3 = i__ + j * a_dim1;
                a[i__3].r = alpha->r, a[i__3].i = alpha->i;
/* L70: */
            }
/* L80: */
        }
        i__1 = min(*m,*n);
        for (i__ = 1; i__ <= i__1; ++i__) {
            i__2 = i__ + i__ * a_dim1;
            a[i__2].r = beta->r, a[i__2].i = beta->i;
/* L90: */
        }
    }

    return 0;

/*     End of ZLASET */

} /* zlaset_ */