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authorshmel1k <shmel1k@ydb.tech>2022-09-02 12:44:59 +0300
committershmel1k <shmel1k@ydb.tech>2022-09-02 12:44:59 +0300
commit90d450f74722da7859d6f510a869f6c6908fd12f (patch)
tree538c718dedc76cdfe37ad6d01ff250dd930d9278 /contrib/libs/clapack/zlahef.c
parent01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff)
downloadydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz
[] add metering mode to CLI
Diffstat (limited to 'contrib/libs/clapack/zlahef.c')
-rw-r--r--contrib/libs/clapack/zlahef.c938
1 files changed, 938 insertions, 0 deletions
diff --git a/contrib/libs/clapack/zlahef.c b/contrib/libs/clapack/zlahef.c
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+++ b/contrib/libs/clapack/zlahef.c
@@ -0,0 +1,938 @@
+/* zlahef.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;
+
+/* Subroutine */ int zlahef_(char *uplo, integer *n, integer *nb, integer *kb,
+ doublecomplex *a, integer *lda, integer *ipiv, doublecomplex *w,
+ integer *ldw, integer *info)
+{
+ /* System generated locals */
+ integer a_dim1, a_offset, w_dim1, w_offset, i__1, i__2, i__3, i__4, i__5;
+ doublereal d__1, d__2, d__3, d__4;
+ doublecomplex z__1, z__2, z__3, z__4;
+
+ /* Builtin functions */
+ double sqrt(doublereal), d_imag(doublecomplex *);
+ void d_cnjg(doublecomplex *, doublecomplex *), z_div(doublecomplex *,
+ doublecomplex *, doublecomplex *);
+
+ /* Local variables */
+ integer j, k;
+ doublereal t, r1;
+ doublecomplex d11, d21, d22;
+ integer jb, jj, kk, jp, kp, kw, kkw, imax, jmax;
+ doublereal alpha;
+ extern logical lsame_(char *, char *);
+ extern /* Subroutine */ int zgemm_(char *, char *, integer *, integer *,
+ integer *, doublecomplex *, doublecomplex *, integer *,
+ doublecomplex *, integer *, doublecomplex *, doublecomplex *,
+ integer *);
+ integer kstep;
+ extern /* Subroutine */ int zgemv_(char *, integer *, integer *,
+ doublecomplex *, doublecomplex *, integer *, doublecomplex *,
+ integer *, doublecomplex *, doublecomplex *, integer *),
+ zcopy_(integer *, doublecomplex *, integer *, doublecomplex *,
+ integer *), zswap_(integer *, doublecomplex *, integer *,
+ doublecomplex *, integer *);
+ doublereal absakk;
+ extern /* Subroutine */ int zdscal_(integer *, doublereal *,
+ doublecomplex *, integer *);
+ doublereal colmax;
+ extern /* Subroutine */ int zlacgv_(integer *, doublecomplex *, integer *)
+ ;
+ extern integer izamax_(integer *, doublecomplex *, integer *);
+ doublereal rowmax;
+
+
+/* -- LAPACK routine (version 3.2) -- */
+/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/* November 2006 */
+
+/* .. Scalar Arguments .. */
+/* .. */
+/* .. Array Arguments .. */
+/* .. */
+
+/* Purpose */
+/* ======= */
+
+/* ZLAHEF computes a partial factorization of a complex Hermitian */
+/* matrix A using the Bunch-Kaufman diagonal pivoting method. The */
+/* partial factorization has the form: */
+
+/* A = ( I U12 ) ( A11 0 ) ( I 0 ) if UPLO = 'U', or: */
+/* ( 0 U22 ) ( 0 D ) ( U12' U22' ) */
+
+/* A = ( L11 0 ) ( D 0 ) ( L11' L21' ) if UPLO = 'L' */
+/* ( L21 I ) ( 0 A22 ) ( 0 I ) */
+
+/* where the order of D is at most NB. The actual order is returned in */
+/* the argument KB, and is either NB or NB-1, or N if N <= NB. */
+/* Note that U' denotes the conjugate transpose of U. */
+
+/* ZLAHEF is an auxiliary routine called by ZHETRF. It uses blocked code */
+/* (calling Level 3 BLAS) to update the submatrix A11 (if UPLO = 'U') or */
+/* A22 (if UPLO = 'L'). */
+
+/* Arguments */
+/* ========= */
+
+/* UPLO (input) CHARACTER*1 */
+/* Specifies whether the upper or lower triangular part of the */
+/* Hermitian matrix A is stored: */
+/* = 'U': Upper triangular */
+/* = 'L': Lower triangular */
+
+/* N (input) INTEGER */
+/* The order of the matrix A. N >= 0. */
+
+/* NB (input) INTEGER */
+/* The maximum number of columns of the matrix A that should be */
+/* factored. NB should be at least 2 to allow for 2-by-2 pivot */
+/* blocks. */
+
+/* KB (output) INTEGER */
+/* The number of columns of A that were actually factored. */
+/* KB is either NB-1 or NB, or N if N <= NB. */
+
+/* A (input/output) COMPLEX*16 array, dimension (LDA,N) */
+/* On entry, the Hermitian matrix A. If UPLO = 'U', the leading */
+/* n-by-n upper triangular part of A contains the upper */
+/* triangular part of the matrix A, and the strictly lower */
+/* triangular part of A is not referenced. If UPLO = 'L', the */
+/* leading n-by-n lower triangular part of A contains the lower */
+/* triangular part of the matrix A, and the strictly upper */
+/* triangular part of A is not referenced. */
+/* On exit, A contains details of the partial factorization. */
+
+/* LDA (input) INTEGER */
+/* The leading dimension of the array A. LDA >= max(1,N). */
+
+/* IPIV (output) INTEGER array, dimension (N) */
+/* Details of the interchanges and the block structure of D. */
+/* If UPLO = 'U', only the last KB elements of IPIV are set; */
+/* if UPLO = 'L', only the first KB elements are set. */
+
+/* If IPIV(k) > 0, then rows and columns k and IPIV(k) were */
+/* interchanged and D(k,k) is a 1-by-1 diagonal block. */
+/* If UPLO = 'U' and IPIV(k) = IPIV(k-1) < 0, then rows and */
+/* columns k-1 and -IPIV(k) were interchanged and D(k-1:k,k-1:k) */
+/* is a 2-by-2 diagonal block. If UPLO = 'L' and IPIV(k) = */
+/* IPIV(k+1) < 0, then rows and columns k+1 and -IPIV(k) were */
+/* interchanged and D(k:k+1,k:k+1) is a 2-by-2 diagonal block. */
+
+/* W (workspace) COMPLEX*16 array, dimension (LDW,NB) */
+
+/* LDW (input) INTEGER */
+/* The leading dimension of the array W. LDW >= max(1,N). */
+
+/* INFO (output) INTEGER */
+/* = 0: successful exit */
+/* > 0: if INFO = k, D(k,k) is exactly zero. The factorization */
+/* has been completed, but the block diagonal matrix D is */
+/* exactly singular. */
+
+/* ===================================================================== */
+
+/* .. Parameters .. */
+/* .. */
+/* .. Local Scalars .. */
+/* .. */
+/* .. External Functions .. */
+/* .. */
+/* .. External Subroutines .. */
+/* .. */
+/* .. Intrinsic Functions .. */
+/* .. */
+/* .. Statement Functions .. */
+/* .. */
+/* .. Statement Function definitions .. */
+/* .. */
+/* .. Executable Statements .. */
+
+ /* Parameter adjustments */
+ a_dim1 = *lda;
+ a_offset = 1 + a_dim1;
+ a -= a_offset;
+ --ipiv;
+ w_dim1 = *ldw;
+ w_offset = 1 + w_dim1;
+ w -= w_offset;
+
+ /* Function Body */
+ *info = 0;
+
+/* Initialize ALPHA for use in choosing pivot block size. */
+
+ alpha = (sqrt(17.) + 1.) / 8.;
+
+ if (lsame_(uplo, "U")) {
+
+/* Factorize the trailing columns of A using the upper triangle */
+/* of A and working backwards, and compute the matrix W = U12*D */
+/* for use in updating A11 (note that conjg(W) is actually stored) */
+
+/* K is the main loop index, decreasing from N in steps of 1 or 2 */
+
+/* KW is the column of W which corresponds to column K of A */
+
+ k = *n;
+L10:
+ kw = *nb + k - *n;
+
+/* Exit from loop */
+
+ if (k <= *n - *nb + 1 && *nb < *n || k < 1) {
+ goto L30;
+ }
+
+/* Copy column K of A to column KW of W and update it */
+
+ i__1 = k - 1;
+ zcopy_(&i__1, &a[k * a_dim1 + 1], &c__1, &w[kw * w_dim1 + 1], &c__1);
+ i__1 = k + kw * w_dim1;
+ i__2 = k + k * a_dim1;
+ d__1 = a[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+ if (k < *n) {
+ i__1 = *n - k;
+ z__1.r = -1., z__1.i = -0.;
+ zgemv_("No transpose", &k, &i__1, &z__1, &a[(k + 1) * a_dim1 + 1],
+ lda, &w[k + (kw + 1) * w_dim1], ldw, &c_b1, &w[kw *
+ w_dim1 + 1], &c__1);
+ i__1 = k + kw * w_dim1;
+ i__2 = k + kw * w_dim1;
+ d__1 = w[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+ }
+
+ kstep = 1;
+
+/* Determine rows and columns to be interchanged and whether */
+/* a 1-by-1 or 2-by-2 pivot block will be used */
+
+ i__1 = k + kw * w_dim1;
+ absakk = (d__1 = w[i__1].r, abs(d__1));
+
+/* IMAX is the row-index of the largest off-diagonal element in */
+/* column K, and COLMAX is its absolute value */
+
+ if (k > 1) {
+ i__1 = k - 1;
+ imax = izamax_(&i__1, &w[kw * w_dim1 + 1], &c__1);
+ i__1 = imax + kw * w_dim1;
+ colmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[imax +
+ kw * w_dim1]), abs(d__2));
+ } else {
+ colmax = 0.;
+ }
+
+ if (max(absakk,colmax) == 0.) {
+
+/* Column K is zero: set INFO and continue */
+
+ if (*info == 0) {
+ *info = k;
+ }
+ kp = k;
+ i__1 = k + k * a_dim1;
+ i__2 = k + k * a_dim1;
+ d__1 = a[i__2].r;
+ a[i__1].r = d__1, a[i__1].i = 0.;
+ } else {
+ if (absakk >= alpha * colmax) {
+
+/* no interchange, use 1-by-1 pivot block */
+
+ kp = k;
+ } else {
+
+/* Copy column IMAX to column KW-1 of W and update it */
+
+ i__1 = imax - 1;
+ zcopy_(&i__1, &a[imax * a_dim1 + 1], &c__1, &w[(kw - 1) *
+ w_dim1 + 1], &c__1);
+ i__1 = imax + (kw - 1) * w_dim1;
+ i__2 = imax + imax * a_dim1;
+ d__1 = a[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+ i__1 = k - imax;
+ zcopy_(&i__1, &a[imax + (imax + 1) * a_dim1], lda, &w[imax +
+ 1 + (kw - 1) * w_dim1], &c__1);
+ i__1 = k - imax;
+ zlacgv_(&i__1, &w[imax + 1 + (kw - 1) * w_dim1], &c__1);
+ if (k < *n) {
+ i__1 = *n - k;
+ z__1.r = -1., z__1.i = -0.;
+ zgemv_("No transpose", &k, &i__1, &z__1, &a[(k + 1) *
+ a_dim1 + 1], lda, &w[imax + (kw + 1) * w_dim1],
+ ldw, &c_b1, &w[(kw - 1) * w_dim1 + 1], &c__1);
+ i__1 = imax + (kw - 1) * w_dim1;
+ i__2 = imax + (kw - 1) * w_dim1;
+ d__1 = w[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+ }
+
+/* JMAX is the column-index of the largest off-diagonal */
+/* element in row IMAX, and ROWMAX is its absolute value */
+
+ i__1 = k - imax;
+ jmax = imax + izamax_(&i__1, &w[imax + 1 + (kw - 1) * w_dim1],
+ &c__1);
+ i__1 = jmax + (kw - 1) * w_dim1;
+ rowmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[
+ jmax + (kw - 1) * w_dim1]), abs(d__2));
+ if (imax > 1) {
+ i__1 = imax - 1;
+ jmax = izamax_(&i__1, &w[(kw - 1) * w_dim1 + 1], &c__1);
+/* Computing MAX */
+ i__1 = jmax + (kw - 1) * w_dim1;
+ d__3 = rowmax, d__4 = (d__1 = w[i__1].r, abs(d__1)) + (
+ d__2 = d_imag(&w[jmax + (kw - 1) * w_dim1]), abs(
+ d__2));
+ rowmax = max(d__3,d__4);
+ }
+
+ if (absakk >= alpha * colmax * (colmax / rowmax)) {
+
+/* no interchange, use 1-by-1 pivot block */
+
+ kp = k;
+ } else /* if(complicated condition) */ {
+ i__1 = imax + (kw - 1) * w_dim1;
+ if ((d__1 = w[i__1].r, abs(d__1)) >= alpha * rowmax) {
+
+/* interchange rows and columns K and IMAX, use 1-by-1 */
+/* pivot block */
+
+ kp = imax;
+
+/* copy column KW-1 of W to column KW */
+
+ zcopy_(&k, &w[(kw - 1) * w_dim1 + 1], &c__1, &w[kw *
+ w_dim1 + 1], &c__1);
+ } else {
+
+/* interchange rows and columns K-1 and IMAX, use 2-by-2 */
+/* pivot block */
+
+ kp = imax;
+ kstep = 2;
+ }
+ }
+ }
+
+ kk = k - kstep + 1;
+ kkw = *nb + kk - *n;
+
+/* Updated column KP is already stored in column KKW of W */
+
+ if (kp != kk) {
+
+/* Copy non-updated column KK to column KP */
+
+ i__1 = kp + kp * a_dim1;
+ i__2 = kk + kk * a_dim1;
+ d__1 = a[i__2].r;
+ a[i__1].r = d__1, a[i__1].i = 0.;
+ i__1 = kk - 1 - kp;
+ zcopy_(&i__1, &a[kp + 1 + kk * a_dim1], &c__1, &a[kp + (kp +
+ 1) * a_dim1], lda);
+ i__1 = kk - 1 - kp;
+ zlacgv_(&i__1, &a[kp + (kp + 1) * a_dim1], lda);
+ i__1 = kp - 1;
+ zcopy_(&i__1, &a[kk * a_dim1 + 1], &c__1, &a[kp * a_dim1 + 1],
+ &c__1);
+
+/* Interchange rows KK and KP in last KK columns of A and W */
+
+ if (kk < *n) {
+ i__1 = *n - kk;
+ zswap_(&i__1, &a[kk + (kk + 1) * a_dim1], lda, &a[kp + (
+ kk + 1) * a_dim1], lda);
+ }
+ i__1 = *n - kk + 1;
+ zswap_(&i__1, &w[kk + kkw * w_dim1], ldw, &w[kp + kkw *
+ w_dim1], ldw);
+ }
+
+ if (kstep == 1) {
+
+/* 1-by-1 pivot block D(k): column KW of W now holds */
+
+/* W(k) = U(k)*D(k) */
+
+/* where U(k) is the k-th column of U */
+
+/* Store U(k) in column k of A */
+
+ zcopy_(&k, &w[kw * w_dim1 + 1], &c__1, &a[k * a_dim1 + 1], &
+ c__1);
+ i__1 = k + k * a_dim1;
+ r1 = 1. / a[i__1].r;
+ i__1 = k - 1;
+ zdscal_(&i__1, &r1, &a[k * a_dim1 + 1], &c__1);
+
+/* Conjugate W(k) */
+
+ i__1 = k - 1;
+ zlacgv_(&i__1, &w[kw * w_dim1 + 1], &c__1);
+ } else {
+
+/* 2-by-2 pivot block D(k): columns KW and KW-1 of W now */
+/* hold */
+
+/* ( W(k-1) W(k) ) = ( U(k-1) U(k) )*D(k) */
+
+/* where U(k) and U(k-1) are the k-th and (k-1)-th columns */
+/* of U */
+
+ if (k > 2) {
+
+/* Store U(k) and U(k-1) in columns k and k-1 of A */
+
+ i__1 = k - 1 + kw * w_dim1;
+ d21.r = w[i__1].r, d21.i = w[i__1].i;
+ d_cnjg(&z__2, &d21);
+ z_div(&z__1, &w[k + kw * w_dim1], &z__2);
+ d11.r = z__1.r, d11.i = z__1.i;
+ z_div(&z__1, &w[k - 1 + (kw - 1) * w_dim1], &d21);
+ d22.r = z__1.r, d22.i = z__1.i;
+ z__1.r = d11.r * d22.r - d11.i * d22.i, z__1.i = d11.r *
+ d22.i + d11.i * d22.r;
+ t = 1. / (z__1.r - 1.);
+ z__2.r = t, z__2.i = 0.;
+ z_div(&z__1, &z__2, &d21);
+ d21.r = z__1.r, d21.i = z__1.i;
+ i__1 = k - 2;
+ for (j = 1; j <= i__1; ++j) {
+ i__2 = j + (k - 1) * a_dim1;
+ i__3 = j + (kw - 1) * w_dim1;
+ z__3.r = d11.r * w[i__3].r - d11.i * w[i__3].i,
+ z__3.i = d11.r * w[i__3].i + d11.i * w[i__3]
+ .r;
+ i__4 = j + kw * w_dim1;
+ z__2.r = z__3.r - w[i__4].r, z__2.i = z__3.i - w[i__4]
+ .i;
+ z__1.r = d21.r * z__2.r - d21.i * z__2.i, z__1.i =
+ d21.r * z__2.i + d21.i * z__2.r;
+ a[i__2].r = z__1.r, a[i__2].i = z__1.i;
+ i__2 = j + k * a_dim1;
+ d_cnjg(&z__2, &d21);
+ i__3 = j + kw * w_dim1;
+ z__4.r = d22.r * w[i__3].r - d22.i * w[i__3].i,
+ z__4.i = d22.r * w[i__3].i + d22.i * w[i__3]
+ .r;
+ i__4 = j + (kw - 1) * w_dim1;
+ z__3.r = z__4.r - w[i__4].r, z__3.i = z__4.i - w[i__4]
+ .i;
+ z__1.r = z__2.r * z__3.r - z__2.i * z__3.i, z__1.i =
+ z__2.r * z__3.i + z__2.i * z__3.r;
+ a[i__2].r = z__1.r, a[i__2].i = z__1.i;
+/* L20: */
+ }
+ }
+
+/* Copy D(k) to A */
+
+ i__1 = k - 1 + (k - 1) * a_dim1;
+ i__2 = k - 1 + (kw - 1) * w_dim1;
+ a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
+ i__1 = k - 1 + k * a_dim1;
+ i__2 = k - 1 + kw * w_dim1;
+ a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
+ i__1 = k + k * a_dim1;
+ i__2 = k + kw * w_dim1;
+ a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
+
+/* Conjugate W(k) and W(k-1) */
+
+ i__1 = k - 1;
+ zlacgv_(&i__1, &w[kw * w_dim1 + 1], &c__1);
+ i__1 = k - 2;
+ zlacgv_(&i__1, &w[(kw - 1) * w_dim1 + 1], &c__1);
+ }
+ }
+
+/* Store details of the interchanges in IPIV */
+
+ if (kstep == 1) {
+ ipiv[k] = kp;
+ } else {
+ ipiv[k] = -kp;
+ ipiv[k - 1] = -kp;
+ }
+
+/* Decrease K and return to the start of the main loop */
+
+ k -= kstep;
+ goto L10;
+
+L30:
+
+/* Update the upper triangle of A11 (= A(1:k,1:k)) as */
+
+/* A11 := A11 - U12*D*U12' = A11 - U12*W' */
+
+/* computing blocks of NB columns at a time (note that conjg(W) is */
+/* actually stored) */
+
+ i__1 = -(*nb);
+ for (j = (k - 1) / *nb * *nb + 1; i__1 < 0 ? j >= 1 : j <= 1; j +=
+ i__1) {
+/* Computing MIN */
+ i__2 = *nb, i__3 = k - j + 1;
+ jb = min(i__2,i__3);
+
+/* Update the upper triangle of the diagonal block */
+
+ i__2 = j + jb - 1;
+ for (jj = j; jj <= i__2; ++jj) {
+ i__3 = jj + jj * a_dim1;
+ i__4 = jj + jj * a_dim1;
+ d__1 = a[i__4].r;
+ a[i__3].r = d__1, a[i__3].i = 0.;
+ i__3 = jj - j + 1;
+ i__4 = *n - k;
+ z__1.r = -1., z__1.i = -0.;
+ zgemv_("No transpose", &i__3, &i__4, &z__1, &a[j + (k + 1) *
+ a_dim1], lda, &w[jj + (kw + 1) * w_dim1], ldw, &c_b1,
+ &a[j + jj * a_dim1], &c__1);
+ i__3 = jj + jj * a_dim1;
+ i__4 = jj + jj * a_dim1;
+ d__1 = a[i__4].r;
+ a[i__3].r = d__1, a[i__3].i = 0.;
+/* L40: */
+ }
+
+/* Update the rectangular superdiagonal block */
+
+ i__2 = j - 1;
+ i__3 = *n - k;
+ z__1.r = -1., z__1.i = -0.;
+ zgemm_("No transpose", "Transpose", &i__2, &jb, &i__3, &z__1, &a[(
+ k + 1) * a_dim1 + 1], lda, &w[j + (kw + 1) * w_dim1], ldw,
+ &c_b1, &a[j * a_dim1 + 1], lda);
+/* L50: */
+ }
+
+/* Put U12 in standard form by partially undoing the interchanges */
+/* in columns k+1:n */
+
+ j = k + 1;
+L60:
+ jj = j;
+ jp = ipiv[j];
+ if (jp < 0) {
+ jp = -jp;
+ ++j;
+ }
+ ++j;
+ if (jp != jj && j <= *n) {
+ i__1 = *n - j + 1;
+ zswap_(&i__1, &a[jp + j * a_dim1], lda, &a[jj + j * a_dim1], lda);
+ }
+ if (j <= *n) {
+ goto L60;
+ }
+
+/* Set KB to the number of columns factorized */
+
+ *kb = *n - k;
+
+ } else {
+
+/* Factorize the leading columns of A using the lower triangle */
+/* of A and working forwards, and compute the matrix W = L21*D */
+/* for use in updating A22 (note that conjg(W) is actually stored) */
+
+/* K is the main loop index, increasing from 1 in steps of 1 or 2 */
+
+ k = 1;
+L70:
+
+/* Exit from loop */
+
+ if (k >= *nb && *nb < *n || k > *n) {
+ goto L90;
+ }
+
+/* Copy column K of A to column K of W and update it */
+
+ i__1 = k + k * w_dim1;
+ i__2 = k + k * a_dim1;
+ d__1 = a[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+ if (k < *n) {
+ i__1 = *n - k;
+ zcopy_(&i__1, &a[k + 1 + k * a_dim1], &c__1, &w[k + 1 + k *
+ w_dim1], &c__1);
+ }
+ i__1 = *n - k + 1;
+ i__2 = k - 1;
+ z__1.r = -1., z__1.i = -0.;
+ zgemv_("No transpose", &i__1, &i__2, &z__1, &a[k + a_dim1], lda, &w[k
+ + w_dim1], ldw, &c_b1, &w[k + k * w_dim1], &c__1);
+ i__1 = k + k * w_dim1;
+ i__2 = k + k * w_dim1;
+ d__1 = w[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+
+ kstep = 1;
+
+/* Determine rows and columns to be interchanged and whether */
+/* a 1-by-1 or 2-by-2 pivot block will be used */
+
+ i__1 = k + k * w_dim1;
+ absakk = (d__1 = w[i__1].r, abs(d__1));
+
+/* IMAX is the row-index of the largest off-diagonal element in */
+/* column K, and COLMAX is its absolute value */
+
+ if (k < *n) {
+ i__1 = *n - k;
+ imax = k + izamax_(&i__1, &w[k + 1 + k * w_dim1], &c__1);
+ i__1 = imax + k * w_dim1;
+ colmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[imax +
+ k * w_dim1]), abs(d__2));
+ } else {
+ colmax = 0.;
+ }
+
+ if (max(absakk,colmax) == 0.) {
+
+/* Column K is zero: set INFO and continue */
+
+ if (*info == 0) {
+ *info = k;
+ }
+ kp = k;
+ i__1 = k + k * a_dim1;
+ i__2 = k + k * a_dim1;
+ d__1 = a[i__2].r;
+ a[i__1].r = d__1, a[i__1].i = 0.;
+ } else {
+ if (absakk >= alpha * colmax) {
+
+/* no interchange, use 1-by-1 pivot block */
+
+ kp = k;
+ } else {
+
+/* Copy column IMAX to column K+1 of W and update it */
+
+ i__1 = imax - k;
+ zcopy_(&i__1, &a[imax + k * a_dim1], lda, &w[k + (k + 1) *
+ w_dim1], &c__1);
+ i__1 = imax - k;
+ zlacgv_(&i__1, &w[k + (k + 1) * w_dim1], &c__1);
+ i__1 = imax + (k + 1) * w_dim1;
+ i__2 = imax + imax * a_dim1;
+ d__1 = a[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+ if (imax < *n) {
+ i__1 = *n - imax;
+ zcopy_(&i__1, &a[imax + 1 + imax * a_dim1], &c__1, &w[
+ imax + 1 + (k + 1) * w_dim1], &c__1);
+ }
+ i__1 = *n - k + 1;
+ i__2 = k - 1;
+ z__1.r = -1., z__1.i = -0.;
+ zgemv_("No transpose", &i__1, &i__2, &z__1, &a[k + a_dim1],
+ lda, &w[imax + w_dim1], ldw, &c_b1, &w[k + (k + 1) *
+ w_dim1], &c__1);
+ i__1 = imax + (k + 1) * w_dim1;
+ i__2 = imax + (k + 1) * w_dim1;
+ d__1 = w[i__2].r;
+ w[i__1].r = d__1, w[i__1].i = 0.;
+
+/* JMAX is the column-index of the largest off-diagonal */
+/* element in row IMAX, and ROWMAX is its absolute value */
+
+ i__1 = imax - k;
+ jmax = k - 1 + izamax_(&i__1, &w[k + (k + 1) * w_dim1], &c__1)
+ ;
+ i__1 = jmax + (k + 1) * w_dim1;
+ rowmax = (d__1 = w[i__1].r, abs(d__1)) + (d__2 = d_imag(&w[
+ jmax + (k + 1) * w_dim1]), abs(d__2));
+ if (imax < *n) {
+ i__1 = *n - imax;
+ jmax = imax + izamax_(&i__1, &w[imax + 1 + (k + 1) *
+ w_dim1], &c__1);
+/* Computing MAX */
+ i__1 = jmax + (k + 1) * w_dim1;
+ d__3 = rowmax, d__4 = (d__1 = w[i__1].r, abs(d__1)) + (
+ d__2 = d_imag(&w[jmax + (k + 1) * w_dim1]), abs(
+ d__2));
+ rowmax = max(d__3,d__4);
+ }
+
+ if (absakk >= alpha * colmax * (colmax / rowmax)) {
+
+/* no interchange, use 1-by-1 pivot block */
+
+ kp = k;
+ } else /* if(complicated condition) */ {
+ i__1 = imax + (k + 1) * w_dim1;
+ if ((d__1 = w[i__1].r, abs(d__1)) >= alpha * rowmax) {
+
+/* interchange rows and columns K and IMAX, use 1-by-1 */
+/* pivot block */
+
+ kp = imax;
+
+/* copy column K+1 of W to column K */
+
+ i__1 = *n - k + 1;
+ zcopy_(&i__1, &w[k + (k + 1) * w_dim1], &c__1, &w[k +
+ k * w_dim1], &c__1);
+ } else {
+
+/* interchange rows and columns K+1 and IMAX, use 2-by-2 */
+/* pivot block */
+
+ kp = imax;
+ kstep = 2;
+ }
+ }
+ }
+
+ kk = k + kstep - 1;
+
+/* Updated column KP is already stored in column KK of W */
+
+ if (kp != kk) {
+
+/* Copy non-updated column KK to column KP */
+
+ i__1 = kp + kp * a_dim1;
+ i__2 = kk + kk * a_dim1;
+ d__1 = a[i__2].r;
+ a[i__1].r = d__1, a[i__1].i = 0.;
+ i__1 = kp - kk - 1;
+ zcopy_(&i__1, &a[kk + 1 + kk * a_dim1], &c__1, &a[kp + (kk +
+ 1) * a_dim1], lda);
+ i__1 = kp - kk - 1;
+ zlacgv_(&i__1, &a[kp + (kk + 1) * a_dim1], lda);
+ if (kp < *n) {
+ i__1 = *n - kp;
+ zcopy_(&i__1, &a[kp + 1 + kk * a_dim1], &c__1, &a[kp + 1
+ + kp * a_dim1], &c__1);
+ }
+
+/* Interchange rows KK and KP in first KK columns of A and W */
+
+ i__1 = kk - 1;
+ zswap_(&i__1, &a[kk + a_dim1], lda, &a[kp + a_dim1], lda);
+ zswap_(&kk, &w[kk + w_dim1], ldw, &w[kp + w_dim1], ldw);
+ }
+
+ if (kstep == 1) {
+
+/* 1-by-1 pivot block D(k): column k of W now holds */
+
+/* W(k) = L(k)*D(k) */
+
+/* where L(k) is the k-th column of L */
+
+/* Store L(k) in column k of A */
+
+ i__1 = *n - k + 1;
+ zcopy_(&i__1, &w[k + k * w_dim1], &c__1, &a[k + k * a_dim1], &
+ c__1);
+ if (k < *n) {
+ i__1 = k + k * a_dim1;
+ r1 = 1. / a[i__1].r;
+ i__1 = *n - k;
+ zdscal_(&i__1, &r1, &a[k + 1 + k * a_dim1], &c__1);
+
+/* Conjugate W(k) */
+
+ i__1 = *n - k;
+ zlacgv_(&i__1, &w[k + 1 + k * w_dim1], &c__1);
+ }
+ } else {
+
+/* 2-by-2 pivot block D(k): columns k and k+1 of W now hold */
+
+/* ( W(k) W(k+1) ) = ( L(k) L(k+1) )*D(k) */
+
+/* where L(k) and L(k+1) are the k-th and (k+1)-th columns */
+/* of L */
+
+ if (k < *n - 1) {
+
+/* Store L(k) and L(k+1) in columns k and k+1 of A */
+
+ i__1 = k + 1 + k * w_dim1;
+ d21.r = w[i__1].r, d21.i = w[i__1].i;
+ z_div(&z__1, &w[k + 1 + (k + 1) * w_dim1], &d21);
+ d11.r = z__1.r, d11.i = z__1.i;
+ d_cnjg(&z__2, &d21);
+ z_div(&z__1, &w[k + k * w_dim1], &z__2);
+ d22.r = z__1.r, d22.i = z__1.i;
+ z__1.r = d11.r * d22.r - d11.i * d22.i, z__1.i = d11.r *
+ d22.i + d11.i * d22.r;
+ t = 1. / (z__1.r - 1.);
+ z__2.r = t, z__2.i = 0.;
+ z_div(&z__1, &z__2, &d21);
+ d21.r = z__1.r, d21.i = z__1.i;
+ i__1 = *n;
+ for (j = k + 2; j <= i__1; ++j) {
+ i__2 = j + k * a_dim1;
+ d_cnjg(&z__2, &d21);
+ i__3 = j + k * w_dim1;
+ z__4.r = d11.r * w[i__3].r - d11.i * w[i__3].i,
+ z__4.i = d11.r * w[i__3].i + d11.i * w[i__3]
+ .r;
+ i__4 = j + (k + 1) * w_dim1;
+ z__3.r = z__4.r - w[i__4].r, z__3.i = z__4.i - w[i__4]
+ .i;
+ z__1.r = z__2.r * z__3.r - z__2.i * z__3.i, z__1.i =
+ z__2.r * z__3.i + z__2.i * z__3.r;
+ a[i__2].r = z__1.r, a[i__2].i = z__1.i;
+ i__2 = j + (k + 1) * a_dim1;
+ i__3 = j + (k + 1) * w_dim1;
+ z__3.r = d22.r * w[i__3].r - d22.i * w[i__3].i,
+ z__3.i = d22.r * w[i__3].i + d22.i * w[i__3]
+ .r;
+ i__4 = j + k * w_dim1;
+ z__2.r = z__3.r - w[i__4].r, z__2.i = z__3.i - w[i__4]
+ .i;
+ z__1.r = d21.r * z__2.r - d21.i * z__2.i, z__1.i =
+ d21.r * z__2.i + d21.i * z__2.r;
+ a[i__2].r = z__1.r, a[i__2].i = z__1.i;
+/* L80: */
+ }
+ }
+
+/* Copy D(k) to A */
+
+ i__1 = k + k * a_dim1;
+ i__2 = k + k * w_dim1;
+ a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
+ i__1 = k + 1 + k * a_dim1;
+ i__2 = k + 1 + k * w_dim1;
+ a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
+ i__1 = k + 1 + (k + 1) * a_dim1;
+ i__2 = k + 1 + (k + 1) * w_dim1;
+ a[i__1].r = w[i__2].r, a[i__1].i = w[i__2].i;
+
+/* Conjugate W(k) and W(k+1) */
+
+ i__1 = *n - k;
+ zlacgv_(&i__1, &w[k + 1 + k * w_dim1], &c__1);
+ i__1 = *n - k - 1;
+ zlacgv_(&i__1, &w[k + 2 + (k + 1) * w_dim1], &c__1);
+ }
+ }
+
+/* Store details of the interchanges in IPIV */
+
+ if (kstep == 1) {
+ ipiv[k] = kp;
+ } else {
+ ipiv[k] = -kp;
+ ipiv[k + 1] = -kp;
+ }
+
+/* Increase K and return to the start of the main loop */
+
+ k += kstep;
+ goto L70;
+
+L90:
+
+/* Update the lower triangle of A22 (= A(k:n,k:n)) as */
+
+/* A22 := A22 - L21*D*L21' = A22 - L21*W' */
+
+/* computing blocks of NB columns at a time (note that conjg(W) is */
+/* actually stored) */
+
+ i__1 = *n;
+ i__2 = *nb;
+ for (j = k; i__2 < 0 ? j >= i__1 : j <= i__1; j += i__2) {
+/* Computing MIN */
+ i__3 = *nb, i__4 = *n - j + 1;
+ jb = min(i__3,i__4);
+
+/* Update the lower triangle of the diagonal block */
+
+ i__3 = j + jb - 1;
+ for (jj = j; jj <= i__3; ++jj) {
+ i__4 = jj + jj * a_dim1;
+ i__5 = jj + jj * a_dim1;
+ d__1 = a[i__5].r;
+ a[i__4].r = d__1, a[i__4].i = 0.;
+ i__4 = j + jb - jj;
+ i__5 = k - 1;
+ z__1.r = -1., z__1.i = -0.;
+ zgemv_("No transpose", &i__4, &i__5, &z__1, &a[jj + a_dim1],
+ lda, &w[jj + w_dim1], ldw, &c_b1, &a[jj + jj * a_dim1]
+, &c__1);
+ i__4 = jj + jj * a_dim1;
+ i__5 = jj + jj * a_dim1;
+ d__1 = a[i__5].r;
+ a[i__4].r = d__1, a[i__4].i = 0.;
+/* L100: */
+ }
+
+/* Update the rectangular subdiagonal block */
+
+ if (j + jb <= *n) {
+ i__3 = *n - j - jb + 1;
+ i__4 = k - 1;
+ z__1.r = -1., z__1.i = -0.;
+ zgemm_("No transpose", "Transpose", &i__3, &jb, &i__4, &z__1,
+ &a[j + jb + a_dim1], lda, &w[j + w_dim1], ldw, &c_b1,
+ &a[j + jb + j * a_dim1], lda);
+ }
+/* L110: */
+ }
+
+/* Put L21 in standard form by partially undoing the interchanges */
+/* in columns 1:k-1 */
+
+ j = k - 1;
+L120:
+ jj = j;
+ jp = ipiv[j];
+ if (jp < 0) {
+ jp = -jp;
+ --j;
+ }
+ --j;
+ if (jp != jj && j >= 1) {
+ zswap_(&j, &a[jp + a_dim1], lda, &a[jj + a_dim1], lda);
+ }
+ if (j >= 1) {
+ goto L120;
+ }
+
+/* Set KB to the number of columns factorized */
+
+ *kb = k - 1;
+
+ }
+ return 0;
+
+/* End of ZLAHEF */
+
+} /* zlahef_ */