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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/dlasyf.c
parent01f64c1ecd0d4ffa9e3a74478335f1745f26cc75 (diff)
downloadydb-90d450f74722da7859d6f510a869f6c6908fd12f.tar.gz
[] add metering mode to CLI
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diff --git a/contrib/libs/clapack/dlasyf.c b/contrib/libs/clapack/dlasyf.c
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+/* dlasyf.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 integer c__1 = 1;
+static doublereal c_b8 = -1.;
+static doublereal c_b9 = 1.;
+
+/* Subroutine */ int dlasyf_(char *uplo, integer *n, integer *nb, integer *kb,
+ doublereal *a, integer *lda, integer *ipiv, doublereal *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;
+
+ /* Builtin functions */
+ double sqrt(doublereal);
+
+ /* Local variables */
+ integer j, k;
+ doublereal t, r1, d11, d21, d22;
+ integer jb, jj, kk, jp, kp, kw, kkw, imax, jmax;
+ doublereal alpha;
+ extern /* Subroutine */ int dscal_(integer *, doublereal *, doublereal *,
+ integer *), dgemm_(char *, char *, integer *, integer *, integer *
+, doublereal *, doublereal *, integer *, doublereal *, integer *,
+ doublereal *, doublereal *, integer *);
+ extern logical lsame_(char *, char *);
+ extern /* Subroutine */ int dgemv_(char *, integer *, integer *,
+ doublereal *, doublereal *, integer *, doublereal *, integer *,
+ doublereal *, doublereal *, integer *), dcopy_(integer *,
+ doublereal *, integer *, doublereal *, integer *), dswap_(integer
+ *, doublereal *, integer *, doublereal *, integer *);
+ integer kstep;
+ doublereal absakk;
+ extern integer idamax_(integer *, doublereal *, integer *);
+ doublereal colmax, rowmax;
+
+
+/* -- LAPACK routine (version 3.2) -- */
+/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
+/* November 2006 */
+
+/* .. Scalar Arguments .. */
+/* .. */
+/* .. Array Arguments .. */
+/* .. */
+
+/* Purpose */
+/* ======= */
+
+/* DLASYF computes a partial factorization of a real symmetric 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. */
+
+/* DLASYF is an auxiliary routine called by DSYTRF. 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 */
+/* symmetric 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) DOUBLE PRECISION array, dimension (LDA,N) */
+/* On entry, the symmetric 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) DOUBLE PRECISION 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 .. */
+/* .. */
+/* .. 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 */
+
+/* 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 */
+
+ dcopy_(&k, &a[k * a_dim1 + 1], &c__1, &w[kw * w_dim1 + 1], &c__1);
+ if (k < *n) {
+ i__1 = *n - k;
+ dgemv_("No transpose", &k, &i__1, &c_b8, &a[(k + 1) * a_dim1 + 1],
+ lda, &w[k + (kw + 1) * w_dim1], ldw, &c_b9, &w[kw *
+ w_dim1 + 1], &c__1);
+ }
+
+ kstep = 1;
+
+/* Determine rows and columns to be interchanged and whether */
+/* a 1-by-1 or 2-by-2 pivot block will be used */
+
+ absakk = (d__1 = w[k + kw * w_dim1], 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 = idamax_(&i__1, &w[kw * w_dim1 + 1], &c__1);
+ colmax = (d__1 = w[imax + kw * w_dim1], abs(d__1));
+ } else {
+ colmax = 0.;
+ }
+
+ if (max(absakk,colmax) == 0.) {
+
+/* Column K is zero: set INFO and continue */
+
+ if (*info == 0) {
+ *info = k;
+ }
+ kp = k;
+ } 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 */
+
+ dcopy_(&imax, &a[imax * a_dim1 + 1], &c__1, &w[(kw - 1) *
+ w_dim1 + 1], &c__1);
+ i__1 = k - imax;
+ dcopy_(&i__1, &a[imax + (imax + 1) * a_dim1], lda, &w[imax +
+ 1 + (kw - 1) * w_dim1], &c__1);
+ if (k < *n) {
+ i__1 = *n - k;
+ dgemv_("No transpose", &k, &i__1, &c_b8, &a[(k + 1) *
+ a_dim1 + 1], lda, &w[imax + (kw + 1) * w_dim1],
+ ldw, &c_b9, &w[(kw - 1) * w_dim1 + 1], &c__1);
+ }
+
+/* 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 + idamax_(&i__1, &w[imax + 1 + (kw - 1) * w_dim1],
+ &c__1);
+ rowmax = (d__1 = w[jmax + (kw - 1) * w_dim1], abs(d__1));
+ if (imax > 1) {
+ i__1 = imax - 1;
+ jmax = idamax_(&i__1, &w[(kw - 1) * w_dim1 + 1], &c__1);
+/* Computing MAX */
+ d__2 = rowmax, d__3 = (d__1 = w[jmax + (kw - 1) * w_dim1],
+ abs(d__1));
+ rowmax = max(d__2,d__3);
+ }
+
+ if (absakk >= alpha * colmax * (colmax / rowmax)) {
+
+/* no interchange, use 1-by-1 pivot block */
+
+ kp = k;
+ } else if ((d__1 = w[imax + (kw - 1) * w_dim1], 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 */
+
+ dcopy_(&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 */
+
+ a[kp + k * a_dim1] = a[kk + k * a_dim1];
+ i__1 = k - 1 - kp;
+ dcopy_(&i__1, &a[kp + 1 + kk * a_dim1], &c__1, &a[kp + (kp +
+ 1) * a_dim1], lda);
+ dcopy_(&kp, &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 */
+
+ i__1 = *n - kk + 1;
+ dswap_(&i__1, &a[kk + kk * a_dim1], lda, &a[kp + kk * a_dim1],
+ lda);
+ i__1 = *n - kk + 1;
+ dswap_(&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 */
+
+ dcopy_(&k, &w[kw * w_dim1 + 1], &c__1, &a[k * a_dim1 + 1], &
+ c__1);
+ r1 = 1. / a[k + k * a_dim1];
+ i__1 = k - 1;
+ dscal_(&i__1, &r1, &a[k * a_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 */
+
+ d21 = w[k - 1 + kw * w_dim1];
+ d11 = w[k + kw * w_dim1] / d21;
+ d22 = w[k - 1 + (kw - 1) * w_dim1] / d21;
+ t = 1. / (d11 * d22 - 1.);
+ d21 = t / d21;
+ i__1 = k - 2;
+ for (j = 1; j <= i__1; ++j) {
+ a[j + (k - 1) * a_dim1] = d21 * (d11 * w[j + (kw - 1)
+ * w_dim1] - w[j + kw * w_dim1]);
+ a[j + k * a_dim1] = d21 * (d22 * w[j + kw * w_dim1] -
+ w[j + (kw - 1) * w_dim1]);
+/* L20: */
+ }
+ }
+
+/* Copy D(k) to A */
+
+ a[k - 1 + (k - 1) * a_dim1] = w[k - 1 + (kw - 1) * w_dim1];
+ a[k - 1 + k * a_dim1] = w[k - 1 + kw * w_dim1];
+ a[k + k * a_dim1] = w[k + kw * w_dim1];
+ }
+ }
+
+/* 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 */
+
+ 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 - j + 1;
+ i__4 = *n - k;
+ dgemv_("No transpose", &i__3, &i__4, &c_b8, &a[j + (k + 1) *
+ a_dim1], lda, &w[jj + (kw + 1) * w_dim1], ldw, &c_b9,
+ &a[j + jj * a_dim1], &c__1);
+/* L40: */
+ }
+
+/* Update the rectangular superdiagonal block */
+
+ i__2 = j - 1;
+ i__3 = *n - k;
+ dgemm_("No transpose", "Transpose", &i__2, &jb, &i__3, &c_b8, &a[(
+ k + 1) * a_dim1 + 1], lda, &w[j + (kw + 1) * w_dim1], ldw,
+ &c_b9, &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;
+ dswap_(&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 */
+
+/* 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 = *n - k + 1;
+ dcopy_(&i__1, &a[k + k * a_dim1], &c__1, &w[k + k * w_dim1], &c__1);
+ i__1 = *n - k + 1;
+ i__2 = k - 1;
+ dgemv_("No transpose", &i__1, &i__2, &c_b8, &a[k + a_dim1], lda, &w[k
+ + w_dim1], ldw, &c_b9, &w[k + k * w_dim1], &c__1);
+
+ kstep = 1;
+
+/* Determine rows and columns to be interchanged and whether */
+/* a 1-by-1 or 2-by-2 pivot block will be used */
+
+ absakk = (d__1 = w[k + k * w_dim1], 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 + idamax_(&i__1, &w[k + 1 + k * w_dim1], &c__1);
+ colmax = (d__1 = w[imax + k * w_dim1], abs(d__1));
+ } else {
+ colmax = 0.;
+ }
+
+ if (max(absakk,colmax) == 0.) {
+
+/* Column K is zero: set INFO and continue */
+
+ if (*info == 0) {
+ *info = k;
+ }
+ kp = k;
+ } 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;
+ dcopy_(&i__1, &a[imax + k * a_dim1], lda, &w[k + (k + 1) *
+ w_dim1], &c__1);
+ i__1 = *n - imax + 1;
+ dcopy_(&i__1, &a[imax + imax * a_dim1], &c__1, &w[imax + (k +
+ 1) * w_dim1], &c__1);
+ i__1 = *n - k + 1;
+ i__2 = k - 1;
+ dgemv_("No transpose", &i__1, &i__2, &c_b8, &a[k + a_dim1],
+ lda, &w[imax + w_dim1], ldw, &c_b9, &w[k + (k + 1) *
+ w_dim1], &c__1);
+
+/* 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 + idamax_(&i__1, &w[k + (k + 1) * w_dim1], &c__1)
+ ;
+ rowmax = (d__1 = w[jmax + (k + 1) * w_dim1], abs(d__1));
+ if (imax < *n) {
+ i__1 = *n - imax;
+ jmax = imax + idamax_(&i__1, &w[imax + 1 + (k + 1) *
+ w_dim1], &c__1);
+/* Computing MAX */
+ d__2 = rowmax, d__3 = (d__1 = w[jmax + (k + 1) * w_dim1],
+ abs(d__1));
+ rowmax = max(d__2,d__3);
+ }
+
+ if (absakk >= alpha * colmax * (colmax / rowmax)) {
+
+/* no interchange, use 1-by-1 pivot block */
+
+ kp = k;
+ } else if ((d__1 = w[imax + (k + 1) * w_dim1], 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;
+ dcopy_(&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 */
+
+ a[kp + k * a_dim1] = a[kk + k * a_dim1];
+ i__1 = kp - k - 1;
+ dcopy_(&i__1, &a[k + 1 + kk * a_dim1], &c__1, &a[kp + (k + 1)
+ * a_dim1], lda);
+ i__1 = *n - kp + 1;
+ dcopy_(&i__1, &a[kp + kk * a_dim1], &c__1, &a[kp + kp *
+ a_dim1], &c__1);
+
+/* Interchange rows KK and KP in first KK columns of A and W */
+
+ dswap_(&kk, &a[kk + a_dim1], lda, &a[kp + a_dim1], lda);
+ dswap_(&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;
+ dcopy_(&i__1, &w[k + k * w_dim1], &c__1, &a[k + k * a_dim1], &
+ c__1);
+ if (k < *n) {
+ r1 = 1. / a[k + k * a_dim1];
+ i__1 = *n - k;
+ dscal_(&i__1, &r1, &a[k + 1 + k * a_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 */
+
+ d21 = w[k + 1 + k * w_dim1];
+ d11 = w[k + 1 + (k + 1) * w_dim1] / d21;
+ d22 = w[k + k * w_dim1] / d21;
+ t = 1. / (d11 * d22 - 1.);
+ d21 = t / d21;
+ i__1 = *n;
+ for (j = k + 2; j <= i__1; ++j) {
+ a[j + k * a_dim1] = d21 * (d11 * w[j + k * w_dim1] -
+ w[j + (k + 1) * w_dim1]);
+ a[j + (k + 1) * a_dim1] = d21 * (d22 * w[j + (k + 1) *
+ w_dim1] - w[j + k * w_dim1]);
+/* L80: */
+ }
+ }
+
+/* Copy D(k) to A */
+
+ a[k + k * a_dim1] = w[k + k * w_dim1];
+ a[k + 1 + k * a_dim1] = w[k + 1 + k * w_dim1];
+ a[k + 1 + (k + 1) * a_dim1] = w[k + 1 + (k + 1) * w_dim1];
+ }
+ }
+
+/* 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 */
+
+ 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 = j + jb - jj;
+ i__5 = k - 1;
+ dgemv_("No transpose", &i__4, &i__5, &c_b8, &a[jj + a_dim1],
+ lda, &w[jj + w_dim1], ldw, &c_b9, &a[jj + jj * a_dim1]
+, &c__1);
+/* L100: */
+ }
+
+/* Update the rectangular subdiagonal block */
+
+ if (j + jb <= *n) {
+ i__3 = *n - j - jb + 1;
+ i__4 = k - 1;
+ dgemm_("No transpose", "Transpose", &i__3, &jb, &i__4, &c_b8,
+ &a[j + jb + a_dim1], lda, &w[j + w_dim1], ldw, &c_b9,
+ &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) {
+ dswap_(&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 DLASYF */
+
+} /* dlasyf_ */