/* zlauum.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"
/* Table of constant values */
static doublecomplex c_b1 = {1.,0.};
static integer c__1 = 1;
static integer c_n1 = -1;
static doublereal c_b21 = 1.;
/* Subroutine */ int zlauum_(char *uplo, integer *n, doublecomplex *a,
integer *lda, integer *info)
{
/* System generated locals */
integer a_dim1, a_offset, i__1, i__2, i__3, i__4;
/* Local variables */
integer i__, ib, nb;
extern logical lsame_(char *, char *);
extern /* Subroutine */ int zgemm_(char *, char *, integer *, integer *,
integer *, doublecomplex *, doublecomplex *, integer *,
doublecomplex *, integer *, doublecomplex *, doublecomplex *,
integer *), zherk_(char *, char *, integer *,
integer *, doublereal *, doublecomplex *, integer *, doublereal *,
doublecomplex *, integer *);
logical upper;
extern /* Subroutine */ int ztrmm_(char *, char *, char *, char *,
integer *, integer *, doublecomplex *, doublecomplex *, integer *,
doublecomplex *, integer *),
zlauu2_(char *, integer *, doublecomplex *, integer *, integer *), xerbla_(char *, integer *);
extern integer ilaenv_(integer *, char *, char *, integer *, integer *,
integer *, integer *);
/* -- LAPACK auxiliary routine (version 3.2) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ZLAUUM computes the product U * U' or L' * L, where the triangular */
/* factor U or L is stored in the upper or lower triangular part of */
/* the array A. */
/* If UPLO = 'U' or 'u' then the upper triangle of the result is stored, */
/* overwriting the factor U in A. */
/* If UPLO = 'L' or 'l' then the lower triangle of the result is stored, */
/* overwriting the factor L in A. */
/* This is the blocked form of the algorithm, calling Level 3 BLAS. */
/* Arguments */
/* ========= */
/* UPLO (input) CHARACTER*1 */
/* Specifies whether the triangular factor stored in the array A */
/* is upper or lower triangular: */
/* = 'U': Upper triangular */
/* = 'L': Lower triangular */
/* N (input) INTEGER */
/* The order of the triangular factor U or L. N >= 0. */
/* A (input/output) COMPLEX*16 array, dimension (LDA,N) */
/* On entry, the triangular factor U or L. */
/* On exit, if UPLO = 'U', the upper triangle of A is */
/* overwritten with the upper triangle of the product U * U'; */
/* if UPLO = 'L', the lower triangle of A is overwritten with */
/* the lower triangle of the product L' * L. */
/* LDA (input) INTEGER */
/* The leading dimension of the array A. LDA >= max(1,N). */
/* INFO (output) INTEGER */
/* = 0: successful exit */
/* < 0: if INFO = -k, the k-th argument had an illegal value */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Executable Statements .. */
/* Test the input parameters. */
/* Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
/* Function Body */
*info = 0;
upper = lsame_(uplo, "U");
if (! upper && ! lsame_(uplo, "L")) {
*info = -1;
} else if (*n < 0) {
*info = -2;
} else if (*lda < max(1,*n)) {
*info = -4;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_("ZLAUUM", &i__1);
return 0;
}
/* Quick return if possible */
if (*n == 0) {
return 0;
}
/* Determine the block size for this environment. */
nb = ilaenv_(&c__1, "ZLAUUM", uplo, n, &c_n1, &c_n1, &c_n1);
if (nb <= 1 || nb >= *n) {
/* Use unblocked code */
zlauu2_(uplo, n, &a[a_offset], lda, info);
} else {
/* Use blocked code */
if (upper) {
/* Compute the product U * U'. */
i__1 = *n;
i__2 = nb;
for (i__ = 1; i__2 < 0 ? i__ >= i__1 : i__ <= i__1; i__ += i__2) {
/* Computing MIN */
i__3 = nb, i__4 = *n - i__ + 1;
ib = min(i__3,i__4);
i__3 = i__ - 1;
ztrmm_("Right", "Upper", "Conjugate transpose", "Non-unit", &
i__3, &ib, &c_b1, &a[i__ + i__ * a_dim1], lda, &a[i__
* a_dim1 + 1], lda);
zlauu2_("Upper", &ib, &a[i__ + i__ * a_dim1], lda, info);
if (i__ + ib <= *n) {
i__3 = i__ - 1;
i__4 = *n - i__ - ib + 1;
zgemm_("No transpose", "Conjugate transpose", &i__3, &ib,
&i__4, &c_b1, &a[(i__ + ib) * a_dim1 + 1], lda, &
a[i__ + (i__ + ib) * a_dim1], lda, &c_b1, &a[i__ *
a_dim1 + 1], lda);
i__3 = *n - i__ - ib + 1;
zherk_("Upper", "No transpose", &ib, &i__3, &c_b21, &a[
i__ + (i__ + ib) * a_dim1], lda, &c_b21, &a[i__ +
i__ * a_dim1], lda);
}
/* L10: */
}
} else {
/* Compute the product L' * L. */
i__2 = *n;
i__1 = nb;
for (i__ = 1; i__1 < 0 ? i__ >= i__2 : i__ <= i__2; i__ += i__1) {
/* Computing MIN */
i__3 = nb, i__4 = *n - i__ + 1;
ib = min(i__3,i__4);
i__3 = i__ - 1;
ztrmm_("Left", "Lower", "Conjugate transpose", "Non-unit", &
ib, &i__3, &c_b1, &a[i__ + i__ * a_dim1], lda, &a[i__
+ a_dim1], lda);
zlauu2_("Lower", &ib, &a[i__ + i__ * a_dim1], lda, info);
if (i__ + ib <= *n) {
i__3 = i__ - 1;
i__4 = *n - i__ - ib + 1;
zgemm_("Conjugate transpose", "No transpose", &ib, &i__3,
&i__4, &c_b1, &a[i__ + ib + i__ * a_dim1], lda, &
a[i__ + ib + a_dim1], lda, &c_b1, &a[i__ + a_dim1]
, lda);
i__3 = *n - i__ - ib + 1;
zherk_("Lower", "Conjugate transpose", &ib, &i__3, &c_b21,
&a[i__ + ib + i__ * a_dim1], lda, &c_b21, &a[i__
+ i__ * a_dim1], lda);
}
/* L20: */
}
}
}
return 0;
/* End of ZLAUUM */
} /* zlauum_ */
