| Rev. | 4 |
|---|---|
| Size | 34,015 bytes |
| Time | 2010-01-31 21:12:08 |
| Author | toshinagata1964 |
| Log Message | AmberTools-1.3 (part) is bundled.
|
Fork/* dlaqr5.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 doublereal c_b7 = 0.;
static doublereal c_b8 = 1.;
static integer c__3 = 3;
static integer c__1 = 1;
static integer c__2 = 2;
/* Subroutine */ int dlaqr5_(logical *wantt, logical *wantz, integer *kacc22,
integer *n, integer *ktop, integer *kbot, integer *nshfts, doublereal
*sr, doublereal *si, doublereal *h__, integer *ldh, integer *iloz,
integer *ihiz, doublereal *z__, integer *ldz, doublereal *v, integer *
ldv, doublereal *u, integer *ldu, integer *nv, doublereal *wv,
integer *ldwv, integer *nh, doublereal *wh, integer *ldwh)
{
/* System generated locals */
integer h_dim1, h_offset, u_dim1, u_offset, v_dim1, v_offset, wh_dim1,
wh_offset, wv_dim1, wv_offset, z_dim1, z_offset, i__1, i__2, i__3,
i__4, i__5, i__6, i__7;
doublereal d__1, d__2, d__3, d__4, d__5;
/* Local variables */
integer i__, j, k, m, i2, j2, i4, j4, k1;
doublereal h11, h12, h21, h22;
integer m22, ns, nu;
doublereal vt[3], scl;
integer kdu, kms;
doublereal ulp;
integer knz, kzs;
doublereal tst1, tst2, beta;
logical blk22, bmp22;
integer mend, jcol, jlen, jbot, mbot;
doublereal swap;
integer jtop, jrow, mtop;
doublereal alpha;
logical accum;
extern /* Subroutine */ int dgemm_(char *, char *, integer *, integer *,
integer *, doublereal *, doublereal *, integer *, doublereal *,
integer *, doublereal *, doublereal *, integer *);
integer ndcol, incol, krcol, nbmps;
extern /* Subroutine */ int dtrmm_(char *, char *, char *, char *,
integer *, integer *, doublereal *, doublereal *, integer *,
doublereal *, integer *), dlaqr1_(
integer *, doublereal *, integer *, doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *), dlabad_(doublereal *,
doublereal *);
extern doublereal dlamch_(char *);
extern /* Subroutine */ int dlarfg_(integer *, doublereal *, doublereal *,
integer *, doublereal *), dlacpy_(char *, integer *, integer *,
doublereal *, integer *, doublereal *, integer *);
doublereal safmin;
extern /* Subroutine */ int dlaset_(char *, integer *, integer *,
doublereal *, doublereal *, doublereal *, integer *);
doublereal safmax, refsum;
integer mstart;
doublereal smlnum;
/* -- LAPACK auxiliary routine (version 3.2) -- */
/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/* November 2006 */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* This auxiliary subroutine called by DLAQR0 performs a */
/* single small-bulge multi-shift QR sweep. */
/* WANTT (input) logical scalar */
/* WANTT = .true. if the quasi-triangular Schur factor */
/* is being computed. WANTT is set to .false. otherwise. */
/* WANTZ (input) logical scalar */
/* WANTZ = .true. if the orthogonal Schur factor is being */
/* computed. WANTZ is set to .false. otherwise. */
/* KACC22 (input) integer with value 0, 1, or 2. */
/* Specifies the computation mode of far-from-diagonal */
/* orthogonal updates. */
/* = 0: DLAQR5 does not accumulate reflections and does not */
/* use matrix-matrix multiply to update far-from-diagonal */
/* matrix entries. */
/* = 1: DLAQR5 accumulates reflections and uses matrix-matrix */
/* multiply to update the far-from-diagonal matrix entries. */
/* = 2: DLAQR5 accumulates reflections, uses matrix-matrix */
/* multiply to update the far-from-diagonal matrix entries, */
/* and takes advantage of 2-by-2 block structure during */
/* matrix multiplies. */
/* N (input) integer scalar */
/* N is the order of the Hessenberg matrix H upon which this */
/* subroutine operates. */
/* KTOP (input) integer scalar */
/* KBOT (input) integer scalar */
/* These are the first and last rows and columns of an */
/* isolated diagonal block upon which the QR sweep is to be */
/* applied. It is assumed without a check that */
/* either KTOP = 1 or H(KTOP,KTOP-1) = 0 */
/* and */
/* either KBOT = N or H(KBOT+1,KBOT) = 0. */
/* NSHFTS (input) integer scalar */
/* NSHFTS gives the number of simultaneous shifts. NSHFTS */
/* must be positive and even. */
/* SR (input/output) DOUBLE PRECISION array of size (NSHFTS) */
/* SI (input/output) DOUBLE PRECISION array of size (NSHFTS) */
/* SR contains the real parts and SI contains the imaginary */
/* parts of the NSHFTS shifts of origin that define the */
/* multi-shift QR sweep. On output SR and SI may be */
/* reordered. */
/* H (input/output) DOUBLE PRECISION array of size (LDH,N) */
/* On input H contains a Hessenberg matrix. On output a */
/* multi-shift QR sweep with shifts SR(J)+i*SI(J) is applied */
/* to the isolated diagonal block in rows and columns KTOP */
/* through KBOT. */
/* LDH (input) integer scalar */
/* LDH is the leading dimension of H just as declared in the */
/* calling procedure. LDH.GE.MAX(1,N). */
/* ILOZ (input) INTEGER */
/* IHIZ (input) INTEGER */
/* Specify the rows of Z to which transformations must be */
/* applied if WANTZ is .TRUE.. 1 .LE. ILOZ .LE. IHIZ .LE. N */
/* Z (input/output) DOUBLE PRECISION array of size (LDZ,IHI) */
/* If WANTZ = .TRUE., then the QR Sweep orthogonal */
/* similarity transformation is accumulated into */
/* Z(ILOZ:IHIZ,ILO:IHI) from the right. */
/* If WANTZ = .FALSE., then Z is unreferenced. */
/* LDZ (input) integer scalar */
/* LDA is the leading dimension of Z just as declared in */
/* the calling procedure. LDZ.GE.N. */
/* V (workspace) DOUBLE PRECISION array of size (LDV,NSHFTS/2) */
/* LDV (input) integer scalar */
/* LDV is the leading dimension of V as declared in the */
/* calling procedure. LDV.GE.3. */
/* U (workspace) DOUBLE PRECISION array of size */
/* (LDU,3*NSHFTS-3) */
/* LDU (input) integer scalar */
/* LDU is the leading dimension of U just as declared in the */
/* in the calling subroutine. LDU.GE.3*NSHFTS-3. */
/* NH (input) integer scalar */
/* NH is the number of columns in array WH available for */
/* workspace. NH.GE.1. */
/* WH (workspace) DOUBLE PRECISION array of size (LDWH,NH) */
/* LDWH (input) integer scalar */
/* Leading dimension of WH just as declared in the */
/* calling procedure. LDWH.GE.3*NSHFTS-3. */
/* NV (input) integer scalar */
/* NV is the number of rows in WV agailable for workspace. */
/* NV.GE.1. */
/* WV (workspace) DOUBLE PRECISION array of size */
/* (LDWV,3*NSHFTS-3) */
/* LDWV (input) integer scalar */
/* LDWV is the leading dimension of WV as declared in the */
/* in the calling subroutine. LDWV.GE.NV. */
/* ================================================================ */
/* Based on contributions by */
/* Karen Braman and Ralph Byers, Department of Mathematics, */
/* University of Kansas, USA */
/* ================================================================ */
/* Reference: */
/* K. Braman, R. Byers and R. Mathias, The Multi-Shift QR */
/* Algorithm Part I: Maintaining Well Focused Shifts, and */
/* Level 3 Performance, SIAM Journal of Matrix Analysis, */
/* volume 23, pages 929--947, 2002. */
/* ================================================================ */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. External Functions .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* .. Local Arrays .. */
/* .. */
/* .. External Subroutines .. */
/* .. */
/* .. Executable Statements .. */
/* ==== If there are no shifts, then there is nothing to do. ==== */
/* Parameter adjustments */
--sr;
--si;
h_dim1 = *ldh;
h_offset = 1 + h_dim1;
h__ -= h_offset;
z_dim1 = *ldz;
z_offset = 1 + z_dim1;
z__ -= z_offset;
v_dim1 = *ldv;
v_offset = 1 + v_dim1;
v -= v_offset;
u_dim1 = *ldu;
u_offset = 1 + u_dim1;
u -= u_offset;
wv_dim1 = *ldwv;
wv_offset = 1 + wv_dim1;
wv -= wv_offset;
wh_dim1 = *ldwh;
wh_offset = 1 + wh_dim1;
wh -= wh_offset;
/* Function Body */
if (*nshfts < 2) {
return 0;
}
/* ==== If the active block is empty or 1-by-1, then there */
/* . is nothing to do. ==== */
if (*ktop >= *kbot) {
return 0;
}
/* ==== Shuffle shifts into pairs of real shifts and pairs */
/* . of complex conjugate shifts assuming complex */
/* . conjugate shifts are already adjacent to one */
/* . another. ==== */
i__1 = *nshfts - 2;
for (i__ = 1; i__ <= i__1; i__ += 2) {
if (si[i__] != -si[i__ + 1]) {
swap = sr[i__];
sr[i__] = sr[i__ + 1];
sr[i__ + 1] = sr[i__ + 2];
sr[i__ + 2] = swap;
swap = si[i__];
si[i__] = si[i__ + 1];
si[i__ + 1] = si[i__ + 2];
si[i__ + 2] = swap;
}
/* L10: */
}
/* ==== NSHFTS is supposed to be even, but if it is odd, */
/* . then simply reduce it by one. The shuffle above */
/* . ensures that the dropped shift is real and that */
/* . the remaining shifts are paired. ==== */
ns = *nshfts - *nshfts % 2;
/* ==== Machine constants for deflation ==== */
safmin = dlamch_("SAFE MINIMUM");
safmax = 1. / safmin;
dlabad_(&safmin, &safmax);
ulp = dlamch_("PRECISION");
smlnum = safmin * ((doublereal) (*n) / ulp);
/* ==== Use accumulated reflections to update far-from-diagonal */
/* . entries ? ==== */
accum = *kacc22 == 1 || *kacc22 == 2;
/* ==== If so, exploit the 2-by-2 block structure? ==== */
blk22 = ns > 2 && *kacc22 == 2;
/* ==== clear trash ==== */
if (*ktop + 2 <= *kbot) {
h__[*ktop + 2 + *ktop * h_dim1] = 0.;
}
/* ==== NBMPS = number of 2-shift bulges in the chain ==== */
nbmps = ns / 2;
/* ==== KDU = width of slab ==== */
kdu = nbmps * 6 - 3;
/* ==== Create and chase chains of NBMPS bulges ==== */
i__1 = *kbot - 2;
i__2 = nbmps * 3 - 2;
for (incol = (1 - nbmps) * 3 + *ktop - 1; i__2 < 0 ? incol >= i__1 :
incol <= i__1; incol += i__2) {
ndcol = incol + kdu;
if (accum) {
dlaset_("ALL", &kdu, &kdu, &c_b7, &c_b8, &u[u_offset], ldu);
}
/* ==== Near-the-diagonal bulge chase. The following loop */
/* . performs the near-the-diagonal part of a small bulge */
/* . multi-shift QR sweep. Each 6*NBMPS-2 column diagonal */
/* . chunk extends from column INCOL to column NDCOL */
/* . (including both column INCOL and column NDCOL). The */
/* . following loop chases a 3*NBMPS column long chain of */
/* . NBMPS bulges 3*NBMPS-2 columns to the right. (INCOL */
/* . may be less than KTOP and and NDCOL may be greater than */
/* . KBOT indicating phantom columns from which to chase */
/* . bulges before they are actually introduced or to which */
/* . to chase bulges beyond column KBOT.) ==== */
/* Computing MIN */
i__4 = incol + nbmps * 3 - 3, i__5 = *kbot - 2;
i__3 = min(i__4,i__5);
for (krcol = incol; krcol <= i__3; ++krcol) {
/* ==== Bulges number MTOP to MBOT are active double implicit */
/* . shift bulges. There may or may not also be small */
/* . 2-by-2 bulge, if there is room. The inactive bulges */
/* . (if any) must wait until the active bulges have moved */
/* . down the diagonal to make room. The phantom matrix */
/* . paradigm described above helps keep track. ==== */
/* Computing MAX */
i__4 = 1, i__5 = (*ktop - 1 - krcol + 2) / 3 + 1;
mtop = max(i__4,i__5);
/* Computing MIN */
i__4 = nbmps, i__5 = (*kbot - krcol) / 3;
mbot = min(i__4,i__5);
m22 = mbot + 1;
bmp22 = mbot < nbmps && krcol + (m22 - 1) * 3 == *kbot - 2;
/* ==== Generate reflections to chase the chain right */
/* . one column. (The minimum value of K is KTOP-1.) ==== */
i__4 = mbot;
for (m = mtop; m <= i__4; ++m) {
k = krcol + (m - 1) * 3;
if (k == *ktop - 1) {
dlaqr1_(&c__3, &h__[*ktop + *ktop * h_dim1], ldh, &sr[(m
<< 1) - 1], &si[(m << 1) - 1], &sr[m * 2], &si[m *
2], &v[m * v_dim1 + 1]);
alpha = v[m * v_dim1 + 1];
dlarfg_(&c__3, &alpha, &v[m * v_dim1 + 2], &c__1, &v[m *
v_dim1 + 1]);
} else {
beta = h__[k + 1 + k * h_dim1];
v[m * v_dim1 + 2] = h__[k + 2 + k * h_dim1];
v[m * v_dim1 + 3] = h__[k + 3 + k * h_dim1];
dlarfg_(&c__3, &beta, &v[m * v_dim1 + 2], &c__1, &v[m *
v_dim1 + 1]);
/* ==== A Bulge may collapse because of vigilant */
/* . deflation or destructive underflow. In the */
/* . underflow case, try the two-small-subdiagonals */
/* . trick to try to reinflate the bulge. ==== */
if (h__[k + 3 + k * h_dim1] != 0. || h__[k + 3 + (k + 1) *
h_dim1] != 0. || h__[k + 3 + (k + 2) * h_dim1] ==
0.) {
/* ==== Typical case: not collapsed (yet). ==== */
h__[k + 1 + k * h_dim1] = beta;
h__[k + 2 + k * h_dim1] = 0.;
h__[k + 3 + k * h_dim1] = 0.;
} else {
/* ==== Atypical case: collapsed. Attempt to */
/* . reintroduce ignoring H(K+1,K) and H(K+2,K). */
/* . If the fill resulting from the new */
/* . reflector is too large, then abandon it. */
/* . Otherwise, use the new one. ==== */
dlaqr1_(&c__3, &h__[k + 1 + (k + 1) * h_dim1], ldh, &
sr[(m << 1) - 1], &si[(m << 1) - 1], &sr[m *
2], &si[m * 2], vt);
alpha = vt[0];
dlarfg_(&c__3, &alpha, &vt[1], &c__1, vt);
refsum = vt[0] * (h__[k + 1 + k * h_dim1] + vt[1] *
h__[k + 2 + k * h_dim1]);
if ((d__1 = h__[k + 2 + k * h_dim1] - refsum * vt[1],
abs(d__1)) + (d__2 = refsum * vt[2], abs(d__2)
) > ulp * ((d__3 = h__[k + k * h_dim1], abs(
d__3)) + (d__4 = h__[k + 1 + (k + 1) * h_dim1]
, abs(d__4)) + (d__5 = h__[k + 2 + (k + 2) *
h_dim1], abs(d__5)))) {
/* ==== Starting a new bulge here would */
/* . create non-negligible fill. Use */
/* . the old one with trepidation. ==== */
h__[k + 1 + k * h_dim1] = beta;
h__[k + 2 + k * h_dim1] = 0.;
h__[k + 3 + k * h_dim1] = 0.;
} else {
/* ==== Stating a new bulge here would */
/* . create only negligible fill. */
/* . Replace the old reflector with */
/* . the new one. ==== */
h__[k + 1 + k * h_dim1] -= refsum;
h__[k + 2 + k * h_dim1] = 0.;
h__[k + 3 + k * h_dim1] = 0.;
v[m * v_dim1 + 1] = vt[0];
v[m * v_dim1 + 2] = vt[1];
v[m * v_dim1 + 3] = vt[2];
}
}
}
/* L20: */
}
/* ==== Generate a 2-by-2 reflection, if needed. ==== */
k = krcol + (m22 - 1) * 3;
if (bmp22) {
if (k == *ktop - 1) {
dlaqr1_(&c__2, &h__[k + 1 + (k + 1) * h_dim1], ldh, &sr[(
m22 << 1) - 1], &si[(m22 << 1) - 1], &sr[m22 * 2],
&si[m22 * 2], &v[m22 * v_dim1 + 1]);
beta = v[m22 * v_dim1 + 1];
dlarfg_(&c__2, &beta, &v[m22 * v_dim1 + 2], &c__1, &v[m22
* v_dim1 + 1]);
} else {
beta = h__[k + 1 + k * h_dim1];
v[m22 * v_dim1 + 2] = h__[k + 2 + k * h_dim1];
dlarfg_(&c__2, &beta, &v[m22 * v_dim1 + 2], &c__1, &v[m22
* v_dim1 + 1]);
h__[k + 1 + k * h_dim1] = beta;
h__[k + 2 + k * h_dim1] = 0.;
}
}
/* ==== Multiply H by reflections from the left ==== */
if (accum) {
jbot = min(ndcol,*kbot);
} else if (*wantt) {
jbot = *n;
} else {
jbot = *kbot;
}
i__4 = jbot;
for (j = max(*ktop,krcol); j <= i__4; ++j) {
/* Computing MIN */
i__5 = mbot, i__6 = (j - krcol + 2) / 3;
mend = min(i__5,i__6);
i__5 = mend;
for (m = mtop; m <= i__5; ++m) {
k = krcol + (m - 1) * 3;
refsum = v[m * v_dim1 + 1] * (h__[k + 1 + j * h_dim1] + v[
m * v_dim1 + 2] * h__[k + 2 + j * h_dim1] + v[m *
v_dim1 + 3] * h__[k + 3 + j * h_dim1]);
h__[k + 1 + j * h_dim1] -= refsum;
h__[k + 2 + j * h_dim1] -= refsum * v[m * v_dim1 + 2];
h__[k + 3 + j * h_dim1] -= refsum * v[m * v_dim1 + 3];
/* L30: */
}
/* L40: */
}
if (bmp22) {
k = krcol + (m22 - 1) * 3;
/* Computing MAX */
i__4 = k + 1;
i__5 = jbot;
for (j = max(i__4,*ktop); j <= i__5; ++j) {
refsum = v[m22 * v_dim1 + 1] * (h__[k + 1 + j * h_dim1] +
v[m22 * v_dim1 + 2] * h__[k + 2 + j * h_dim1]);
h__[k + 1 + j * h_dim1] -= refsum;
h__[k + 2 + j * h_dim1] -= refsum * v[m22 * v_dim1 + 2];
/* L50: */
}
}
/* ==== Multiply H by reflections from the right. */
/* . Delay filling in the last row until the */
/* . vigilant deflation check is complete. ==== */
if (accum) {
jtop = max(*ktop,incol);
} else if (*wantt) {
jtop = 1;
} else {
jtop = *ktop;
}
i__5 = mbot;
for (m = mtop; m <= i__5; ++m) {
if (v[m * v_dim1 + 1] != 0.) {
k = krcol + (m - 1) * 3;
/* Computing MIN */
i__6 = *kbot, i__7 = k + 3;
i__4 = min(i__6,i__7);
for (j = jtop; j <= i__4; ++j) {
refsum = v[m * v_dim1 + 1] * (h__[j + (k + 1) *
h_dim1] + v[m * v_dim1 + 2] * h__[j + (k + 2)
* h_dim1] + v[m * v_dim1 + 3] * h__[j + (k +
3) * h_dim1]);
h__[j + (k + 1) * h_dim1] -= refsum;
h__[j + (k + 2) * h_dim1] -= refsum * v[m * v_dim1 +
2];
h__[j + (k + 3) * h_dim1] -= refsum * v[m * v_dim1 +
3];
/* L60: */
}
if (accum) {
/* ==== Accumulate U. (If necessary, update Z later */
/* . with with an efficient matrix-matrix */
/* . multiply.) ==== */
kms = k - incol;
/* Computing MAX */
i__4 = 1, i__6 = *ktop - incol;
i__7 = kdu;
for (j = max(i__4,i__6); j <= i__7; ++j) {
refsum = v[m * v_dim1 + 1] * (u[j + (kms + 1) *
u_dim1] + v[m * v_dim1 + 2] * u[j + (kms
+ 2) * u_dim1] + v[m * v_dim1 + 3] * u[j
+ (kms + 3) * u_dim1]);
u[j + (kms + 1) * u_dim1] -= refsum;
u[j + (kms + 2) * u_dim1] -= refsum * v[m *
v_dim1 + 2];
u[j + (kms + 3) * u_dim1] -= refsum * v[m *
v_dim1 + 3];
/* L70: */
}
} else if (*wantz) {
/* ==== U is not accumulated, so update Z */
/* . now by multiplying by reflections */
/* . from the right. ==== */
i__7 = *ihiz;
for (j = *iloz; j <= i__7; ++j) {
refsum = v[m * v_dim1 + 1] * (z__[j + (k + 1) *
z_dim1] + v[m * v_dim1 + 2] * z__[j + (k
+ 2) * z_dim1] + v[m * v_dim1 + 3] * z__[
j + (k + 3) * z_dim1]);
z__[j + (k + 1) * z_dim1] -= refsum;
z__[j + (k + 2) * z_dim1] -= refsum * v[m *
v_dim1 + 2];
z__[j + (k + 3) * z_dim1] -= refsum * v[m *
v_dim1 + 3];
/* L80: */
}
}
}
/* L90: */
}
/* ==== Special case: 2-by-2 reflection (if needed) ==== */
k = krcol + (m22 - 1) * 3;
if (bmp22 && v[m22 * v_dim1 + 1] != 0.) {
/* Computing MIN */
i__7 = *kbot, i__4 = k + 3;
i__5 = min(i__7,i__4);
for (j = jtop; j <= i__5; ++j) {
refsum = v[m22 * v_dim1 + 1] * (h__[j + (k + 1) * h_dim1]
+ v[m22 * v_dim1 + 2] * h__[j + (k + 2) * h_dim1])
;
h__[j + (k + 1) * h_dim1] -= refsum;
h__[j + (k + 2) * h_dim1] -= refsum * v[m22 * v_dim1 + 2];
/* L100: */
}
if (accum) {
kms = k - incol;
/* Computing MAX */
i__5 = 1, i__7 = *ktop - incol;
i__4 = kdu;
for (j = max(i__5,i__7); j <= i__4; ++j) {
refsum = v[m22 * v_dim1 + 1] * (u[j + (kms + 1) *
u_dim1] + v[m22 * v_dim1 + 2] * u[j + (kms +
2) * u_dim1]);
u[j + (kms + 1) * u_dim1] -= refsum;
u[j + (kms + 2) * u_dim1] -= refsum * v[m22 * v_dim1
+ 2];
/* L110: */
}
} else if (*wantz) {
i__4 = *ihiz;
for (j = *iloz; j <= i__4; ++j) {
refsum = v[m22 * v_dim1 + 1] * (z__[j + (k + 1) *
z_dim1] + v[m22 * v_dim1 + 2] * z__[j + (k +
2) * z_dim1]);
z__[j + (k + 1) * z_dim1] -= refsum;
z__[j + (k + 2) * z_dim1] -= refsum * v[m22 * v_dim1
+ 2];
/* L120: */
}
}
}
/* ==== Vigilant deflation check ==== */
mstart = mtop;
if (krcol + (mstart - 1) * 3 < *ktop) {
++mstart;
}
mend = mbot;
if (bmp22) {
++mend;
}
if (krcol == *kbot - 2) {
++mend;
}
i__4 = mend;
for (m = mstart; m <= i__4; ++m) {
/* Computing MIN */
i__5 = *kbot - 1, i__7 = krcol + (m - 1) * 3;
k = min(i__5,i__7);
/* ==== The following convergence test requires that */
/* . the tradition small-compared-to-nearby-diagonals */
/* . criterion and the Ahues & Tisseur (LAWN 122, 1997) */
/* . criteria both be satisfied. The latter improves */
/* . accuracy in some examples. Falling back on an */
/* . alternate convergence criterion when TST1 or TST2 */
/* . is zero (as done here) is traditional but probably */
/* . unnecessary. ==== */
if (h__[k + 1 + k * h_dim1] != 0.) {
tst1 = (d__1 = h__[k + k * h_dim1], abs(d__1)) + (d__2 =
h__[k + 1 + (k + 1) * h_dim1], abs(d__2));
if (tst1 == 0.) {
if (k >= *ktop + 1) {
tst1 += (d__1 = h__[k + (k - 1) * h_dim1], abs(
d__1));
}
if (k >= *ktop + 2) {
tst1 += (d__1 = h__[k + (k - 2) * h_dim1], abs(
d__1));
}
if (k >= *ktop + 3) {
tst1 += (d__1 = h__[k + (k - 3) * h_dim1], abs(
d__1));
}
if (k <= *kbot - 2) {
tst1 += (d__1 = h__[k + 2 + (k + 1) * h_dim1],
abs(d__1));
}
if (k <= *kbot - 3) {
tst1 += (d__1 = h__[k + 3 + (k + 1) * h_dim1],
abs(d__1));
}
if (k <= *kbot - 4) {
tst1 += (d__1 = h__[k + 4 + (k + 1) * h_dim1],
abs(d__1));
}
}
/* Computing MAX */
d__2 = smlnum, d__3 = ulp * tst1;
if ((d__1 = h__[k + 1 + k * h_dim1], abs(d__1)) <= max(
d__2,d__3)) {
/* Computing MAX */
d__3 = (d__1 = h__[k + 1 + k * h_dim1], abs(d__1)),
d__4 = (d__2 = h__[k + (k + 1) * h_dim1], abs(
d__2));
h12 = max(d__3,d__4);
/* Computing MIN */
d__3 = (d__1 = h__[k + 1 + k * h_dim1], abs(d__1)),
d__4 = (d__2 = h__[k + (k + 1) * h_dim1], abs(
d__2));
h21 = min(d__3,d__4);
/* Computing MAX */
d__3 = (d__1 = h__[k + 1 + (k + 1) * h_dim1], abs(
d__1)), d__4 = (d__2 = h__[k + k * h_dim1] -
h__[k + 1 + (k + 1) * h_dim1], abs(d__2));
h11 = max(d__3,d__4);
/* Computing MIN */
d__3 = (d__1 = h__[k + 1 + (k + 1) * h_dim1], abs(
d__1)), d__4 = (d__2 = h__[k + k * h_dim1] -
h__[k + 1 + (k + 1) * h_dim1], abs(d__2));
h22 = min(d__3,d__4);
scl = h11 + h12;
tst2 = h22 * (h11 / scl);
/* Computing MAX */
d__1 = smlnum, d__2 = ulp * tst2;
if (tst2 == 0. || h21 * (h12 / scl) <= max(d__1,d__2))
{
h__[k + 1 + k * h_dim1] = 0.;
}
}
}
/* L130: */
}
/* ==== Fill in the last row of each bulge. ==== */
/* Computing MIN */
i__4 = nbmps, i__5 = (*kbot - krcol - 1) / 3;
mend = min(i__4,i__5);
i__4 = mend;
for (m = mtop; m <= i__4; ++m) {
k = krcol + (m - 1) * 3;
refsum = v[m * v_dim1 + 1] * v[m * v_dim1 + 3] * h__[k + 4 + (
k + 3) * h_dim1];
h__[k + 4 + (k + 1) * h_dim1] = -refsum;
h__[k + 4 + (k + 2) * h_dim1] = -refsum * v[m * v_dim1 + 2];
h__[k + 4 + (k + 3) * h_dim1] -= refsum * v[m * v_dim1 + 3];
/* L140: */
}
/* ==== End of near-the-diagonal bulge chase. ==== */
/* L150: */
}
/* ==== Use U (if accumulated) to update far-from-diagonal */
/* . entries in H. If required, use U to update Z as */
/* . well. ==== */
if (accum) {
if (*wantt) {
jtop = 1;
jbot = *n;
} else {
jtop = *ktop;
jbot = *kbot;
}
if (! blk22 || incol < *ktop || ndcol > *kbot || ns <= 2) {
/* ==== Updates not exploiting the 2-by-2 block */
/* . structure of U. K1 and NU keep track of */
/* . the location and size of U in the special */
/* . cases of introducing bulges and chasing */
/* . bulges off the bottom. In these special */
/* . cases and in case the number of shifts */
/* . is NS = 2, there is no 2-by-2 block */
/* . structure to exploit. ==== */
/* Computing MAX */
i__3 = 1, i__4 = *ktop - incol;
k1 = max(i__3,i__4);
/* Computing MAX */
i__3 = 0, i__4 = ndcol - *kbot;
nu = kdu - max(i__3,i__4) - k1 + 1;
/* ==== Horizontal Multiply ==== */
i__3 = jbot;
i__4 = *nh;
for (jcol = min(ndcol,*kbot) + 1; i__4 < 0 ? jcol >= i__3 :
jcol <= i__3; jcol += i__4) {
/* Computing MIN */
i__5 = *nh, i__7 = jbot - jcol + 1;
jlen = min(i__5,i__7);
dgemm_("C", "N", &nu, &jlen, &nu, &c_b8, &u[k1 + k1 *
u_dim1], ldu, &h__[incol + k1 + jcol * h_dim1],
ldh, &c_b7, &wh[wh_offset], ldwh);
dlacpy_("ALL", &nu, &jlen, &wh[wh_offset], ldwh, &h__[
incol + k1 + jcol * h_dim1], ldh);
/* L160: */
}
/* ==== Vertical multiply ==== */
i__4 = max(*ktop,incol) - 1;
i__3 = *nv;
for (jrow = jtop; i__3 < 0 ? jrow >= i__4 : jrow <= i__4;
jrow += i__3) {
/* Computing MIN */
i__5 = *nv, i__7 = max(*ktop,incol) - jrow;
jlen = min(i__5,i__7);
dgemm_("N", "N", &jlen, &nu, &nu, &c_b8, &h__[jrow + (
incol + k1) * h_dim1], ldh, &u[k1 + k1 * u_dim1],
ldu, &c_b7, &wv[wv_offset], ldwv);
dlacpy_("ALL", &jlen, &nu, &wv[wv_offset], ldwv, &h__[
jrow + (incol + k1) * h_dim1], ldh);
/* L170: */
}
/* ==== Z multiply (also vertical) ==== */
if (*wantz) {
i__3 = *ihiz;
i__4 = *nv;
for (jrow = *iloz; i__4 < 0 ? jrow >= i__3 : jrow <= i__3;
jrow += i__4) {
/* Computing MIN */
i__5 = *nv, i__7 = *ihiz - jrow + 1;
jlen = min(i__5,i__7);
dgemm_("N", "N", &jlen, &nu, &nu, &c_b8, &z__[jrow + (
incol + k1) * z_dim1], ldz, &u[k1 + k1 *
u_dim1], ldu, &c_b7, &wv[wv_offset], ldwv);
dlacpy_("ALL", &jlen, &nu, &wv[wv_offset], ldwv, &z__[
jrow + (incol + k1) * z_dim1], ldz)
;
/* L180: */
}
}
} else {
/* ==== Updates exploiting U's 2-by-2 block structure. */
/* . (I2, I4, J2, J4 are the last rows and columns */
/* . of the blocks.) ==== */
i2 = (kdu + 1) / 2;
i4 = kdu;
j2 = i4 - i2;
j4 = kdu;
/* ==== KZS and KNZ deal with the band of zeros */
/* . along the diagonal of one of the triangular */
/* . blocks. ==== */
kzs = j4 - j2 - (ns + 1);
knz = ns + 1;
/* ==== Horizontal multiply ==== */
i__4 = jbot;
i__3 = *nh;
for (jcol = min(ndcol,*kbot) + 1; i__3 < 0 ? jcol >= i__4 :
jcol <= i__4; jcol += i__3) {
/* Computing MIN */
i__5 = *nh, i__7 = jbot - jcol + 1;
jlen = min(i__5,i__7);
/* ==== Copy bottom of H to top+KZS of scratch ==== */
/* (The first KZS rows get multiplied by zero.) ==== */
dlacpy_("ALL", &knz, &jlen, &h__[incol + 1 + j2 + jcol *
h_dim1], ldh, &wh[kzs + 1 + wh_dim1], ldwh);
/* ==== Multiply by U21' ==== */
dlaset_("ALL", &kzs, &jlen, &c_b7, &c_b7, &wh[wh_offset],
ldwh);
dtrmm_("L", "U", "C", "N", &knz, &jlen, &c_b8, &u[j2 + 1
+ (kzs + 1) * u_dim1], ldu, &wh[kzs + 1 + wh_dim1]
, ldwh);
/* ==== Multiply top of H by U11' ==== */
dgemm_("C", "N", &i2, &jlen, &j2, &c_b8, &u[u_offset],
ldu, &h__[incol + 1 + jcol * h_dim1], ldh, &c_b8,
&wh[wh_offset], ldwh);
/* ==== Copy top of H to bottom of WH ==== */
dlacpy_("ALL", &j2, &jlen, &h__[incol + 1 + jcol * h_dim1]
, ldh, &wh[i2 + 1 + wh_dim1], ldwh);
/* ==== Multiply by U21' ==== */
dtrmm_("L", "L", "C", "N", &j2, &jlen, &c_b8, &u[(i2 + 1)
* u_dim1 + 1], ldu, &wh[i2 + 1 + wh_dim1], ldwh);
/* ==== Multiply by U22 ==== */
i__5 = i4 - i2;
i__7 = j4 - j2;
dgemm_("C", "N", &i__5, &jlen, &i__7, &c_b8, &u[j2 + 1 + (
i2 + 1) * u_dim1], ldu, &h__[incol + 1 + j2 +
jcol * h_dim1], ldh, &c_b8, &wh[i2 + 1 + wh_dim1],
ldwh);
/* ==== Copy it back ==== */
dlacpy_("ALL", &kdu, &jlen, &wh[wh_offset], ldwh, &h__[
incol + 1 + jcol * h_dim1], ldh);
/* L190: */
}
/* ==== Vertical multiply ==== */
i__3 = max(incol,*ktop) - 1;
i__4 = *nv;
for (jrow = jtop; i__4 < 0 ? jrow >= i__3 : jrow <= i__3;
jrow += i__4) {
/* Computing MIN */
i__5 = *nv, i__7 = max(incol,*ktop) - jrow;
jlen = min(i__5,i__7);
/* ==== Copy right of H to scratch (the first KZS */
/* . columns get multiplied by zero) ==== */
dlacpy_("ALL", &jlen, &knz, &h__[jrow + (incol + 1 + j2) *
h_dim1], ldh, &wv[(kzs + 1) * wv_dim1 + 1], ldwv);
/* ==== Multiply by U21 ==== */
dlaset_("ALL", &jlen, &kzs, &c_b7, &c_b7, &wv[wv_offset],
ldwv);
dtrmm_("R", "U", "N", "N", &jlen, &knz, &c_b8, &u[j2 + 1
+ (kzs + 1) * u_dim1], ldu, &wv[(kzs + 1) *
wv_dim1 + 1], ldwv);
/* ==== Multiply by U11 ==== */
dgemm_("N", "N", &jlen, &i2, &j2, &c_b8, &h__[jrow + (
incol + 1) * h_dim1], ldh, &u[u_offset], ldu, &
c_b8, &wv[wv_offset], ldwv);
/* ==== Copy left of H to right of scratch ==== */
dlacpy_("ALL", &jlen, &j2, &h__[jrow + (incol + 1) *
h_dim1], ldh, &wv[(i2 + 1) * wv_dim1 + 1], ldwv);
/* ==== Multiply by U21 ==== */
i__5 = i4 - i2;
dtrmm_("R", "L", "N", "N", &jlen, &i__5, &c_b8, &u[(i2 +
1) * u_dim1 + 1], ldu, &wv[(i2 + 1) * wv_dim1 + 1]
, ldwv);
/* ==== Multiply by U22 ==== */
i__5 = i4 - i2;
i__7 = j4 - j2;
dgemm_("N", "N", &jlen, &i__5, &i__7, &c_b8, &h__[jrow + (
incol + 1 + j2) * h_dim1], ldh, &u[j2 + 1 + (i2 +
1) * u_dim1], ldu, &c_b8, &wv[(i2 + 1) * wv_dim1
+ 1], ldwv);
/* ==== Copy it back ==== */
dlacpy_("ALL", &jlen, &kdu, &wv[wv_offset], ldwv, &h__[
jrow + (incol + 1) * h_dim1], ldh);
/* L200: */
}
/* ==== Multiply Z (also vertical) ==== */
if (*wantz) {
i__4 = *ihiz;
i__3 = *nv;
for (jrow = *iloz; i__3 < 0 ? jrow >= i__4 : jrow <= i__4;
jrow += i__3) {
/* Computing MIN */
i__5 = *nv, i__7 = *ihiz - jrow + 1;
jlen = min(i__5,i__7);
/* ==== Copy right of Z to left of scratch (first */
/* . KZS columns get multiplied by zero) ==== */
dlacpy_("ALL", &jlen, &knz, &z__[jrow + (incol + 1 +
j2) * z_dim1], ldz, &wv[(kzs + 1) * wv_dim1 +
1], ldwv);
/* ==== Multiply by U12 ==== */
dlaset_("ALL", &jlen, &kzs, &c_b7, &c_b7, &wv[
wv_offset], ldwv);
dtrmm_("R", "U", "N", "N", &jlen, &knz, &c_b8, &u[j2
+ 1 + (kzs + 1) * u_dim1], ldu, &wv[(kzs + 1)
* wv_dim1 + 1], ldwv);
/* ==== Multiply by U11 ==== */
dgemm_("N", "N", &jlen, &i2, &j2, &c_b8, &z__[jrow + (
incol + 1) * z_dim1], ldz, &u[u_offset], ldu,
&c_b8, &wv[wv_offset], ldwv);
/* ==== Copy left of Z to right of scratch ==== */
dlacpy_("ALL", &jlen, &j2, &z__[jrow + (incol + 1) *
z_dim1], ldz, &wv[(i2 + 1) * wv_dim1 + 1],
ldwv);
/* ==== Multiply by U21 ==== */
i__5 = i4 - i2;
dtrmm_("R", "L", "N", "N", &jlen, &i__5, &c_b8, &u[(
i2 + 1) * u_dim1 + 1], ldu, &wv[(i2 + 1) *
wv_dim1 + 1], ldwv);
/* ==== Multiply by U22 ==== */
i__5 = i4 - i2;
i__7 = j4 - j2;
dgemm_("N", "N", &jlen, &i__5, &i__7, &c_b8, &z__[
jrow + (incol + 1 + j2) * z_dim1], ldz, &u[j2
+ 1 + (i2 + 1) * u_dim1], ldu, &c_b8, &wv[(i2
+ 1) * wv_dim1 + 1], ldwv);
/* ==== Copy the result back to Z ==== */
dlacpy_("ALL", &jlen, &kdu, &wv[wv_offset], ldwv, &
z__[jrow + (incol + 1) * z_dim1], ldz);
/* L210: */
}
}
}
}
/* L220: */
}
/* ==== End of DLAQR5 ==== */
return 0;
} /* dlaqr5_ */