717 lines
21 KiB
C++
717 lines
21 KiB
C++
/* fortran/dlasq2.f -- translated by f2c (version 20200916).
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You must link the resulting object file with libf2c:
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on Microsoft Windows system, link with libf2c.lib;
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on Linux or Unix systems, link with .../path/to/libf2c.a -lm
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or, if you install libf2c.a in a standard place, with -lf2c -lm
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-- in that order, at the end of the command line, as in
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cc *.o -lf2c -lm
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Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
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http://www.netlib.org/f2c/libf2c.zip
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*/
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#ifdef __cplusplus
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extern "C" {
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#endif
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#include "lmp_f2c.h"
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/* Table of constant values */
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static integer c__1 = 1;
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static integer c__2 = 2;
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static integer c__10 = 10;
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static integer c__3 = 3;
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static integer c__4 = 4;
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/* > \brief \b DLASQ2 computes all the eigenvalues of the symmetric positive definite tridiagonal matrix assoc
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iated with the qd Array Z to high relative accuracy. Used by sbdsqr and sstegr. */
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/* =========== DOCUMENTATION =========== */
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/* Online html documentation available at */
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/* http://www.netlib.org/lapack/explore-html/ */
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/* > \htmlonly */
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/* > Download DLASQ2 + dependencies */
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/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlasq2.
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f"> */
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/* > [TGZ]</a> */
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/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlasq2.
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f"> */
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/* > [ZIP]</a> */
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/* > <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlasq2.
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f"> */
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/* > [TXT]</a> */
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/* > \endhtmlonly */
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/* Definition: */
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/* =========== */
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/* SUBROUTINE DLASQ2( N, Z, INFO ) */
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/* .. Scalar Arguments .. */
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/* INTEGER INFO, N */
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/* .. */
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/* .. Array Arguments .. */
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/* DOUBLE PRECISION Z( * ) */
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/* .. */
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/* > \par Purpose: */
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/* ============= */
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/* > */
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/* > \verbatim */
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/* > */
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/* > DLASQ2 computes all the eigenvalues of the symmetric positive */
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/* > definite tridiagonal matrix associated with the qd array Z to high */
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/* > relative accuracy are computed to high relative accuracy, in the */
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/* > absence of denormalization, underflow and overflow. */
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/* > */
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/* > To see the relation of Z to the tridiagonal matrix, let L be a */
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/* > unit lower bidiagonal matrix with subdiagonals Z(2,4,6,,..) and */
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/* > let U be an upper bidiagonal matrix with 1's above and diagonal */
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/* > Z(1,3,5,,..). The tridiagonal is L*U or, if you prefer, the */
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/* > symmetric tridiagonal to which it is similar. */
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/* > */
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/* > Note : DLASQ2 defines a logical variable, IEEE, which is true */
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/* > on machines which follow ieee-754 floating-point standard in their */
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/* > handling of infinities and NaNs, and false otherwise. This variable */
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/* > is passed to DLASQ3. */
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/* > \endverbatim */
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/* Arguments: */
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/* ========== */
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/* > \param[in] N */
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/* > \verbatim */
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/* > N is INTEGER */
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/* > The number of rows and columns in the matrix. N >= 0. */
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/* > \endverbatim */
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/* > */
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/* > \param[in,out] Z */
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/* > \verbatim */
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/* > Z is DOUBLE PRECISION array, dimension ( 4*N ) */
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/* > On entry Z holds the qd array. On exit, entries 1 to N hold */
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/* > the eigenvalues in decreasing order, Z( 2*N+1 ) holds the */
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/* > trace, and Z( 2*N+2 ) holds the sum of the eigenvalues. If */
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/* > N > 2, then Z( 2*N+3 ) holds the iteration count, Z( 2*N+4 ) */
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/* > holds NDIVS/NIN^2, and Z( 2*N+5 ) holds the percentage of */
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/* > shifts that failed. */
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/* > \endverbatim */
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/* > */
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/* > \param[out] INFO */
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/* > \verbatim */
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/* > INFO is INTEGER */
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/* > = 0: successful exit */
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/* > < 0: if the i-th argument is a scalar and had an illegal */
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/* > value, then INFO = -i, if the i-th argument is an */
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/* > array and the j-entry had an illegal value, then */
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/* > INFO = -(i*100+j) */
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/* > > 0: the algorithm failed */
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/* > = 1, a split was marked by a positive value in E */
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/* > = 2, current block of Z not diagonalized after 100*N */
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/* > iterations (in inner while loop). On exit Z holds */
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/* > a qd array with the same eigenvalues as the given Z. */
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/* > = 3, termination criterion of outer while loop not met */
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/* > (program created more than N unreduced blocks) */
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/* > \endverbatim */
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/* Authors: */
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/* ======== */
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/* > \author Univ. of Tennessee */
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/* > \author Univ. of California Berkeley */
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/* > \author Univ. of Colorado Denver */
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/* > \author NAG Ltd. */
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/* > \ingroup auxOTHERcomputational */
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/* > \par Further Details: */
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/* ===================== */
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/* > */
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/* > \verbatim */
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/* > */
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/* > Local Variables: I0:N0 defines a current unreduced segment of Z. */
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/* > The shifts are accumulated in SIGMA. Iteration count is in ITER. */
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/* > Ping-pong is controlled by PP (alternates between 0 and 1). */
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/* > \endverbatim */
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/* > */
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/* ===================================================================== */
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/* Subroutine */ int dlasq2_(integer *n, doublereal *z__, integer *info)
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{
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/* System generated locals */
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integer i__1, i__2, i__3;
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doublereal d__1, d__2;
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/* Builtin functions */
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double sqrt(doublereal);
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/* Local variables */
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doublereal d__, e, g;
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integer k;
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doublereal s, t;
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integer i0, i1, i4, n0, n1;
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doublereal dn;
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integer pp;
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doublereal dn1, dn2, dee, eps, tau, tol;
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integer ipn4;
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doublereal tol2;
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logical ieee;
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integer nbig;
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doublereal dmin__, emin, emax;
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integer kmin, ndiv, iter;
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doublereal qmin, temp, qmax, zmax;
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integer splt;
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doublereal dmin1, dmin2;
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integer nfail;
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doublereal desig, trace, sigma;
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integer iinfo;
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doublereal tempe, tempq;
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integer ttype;
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extern /* Subroutine */ int dlasq3_(integer *, integer *, doublereal *,
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integer *, doublereal *, doublereal *, doublereal *, doublereal *,
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integer *, integer *, integer *, logical *, integer *,
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doublereal *, doublereal *, doublereal *, doublereal *,
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doublereal *, doublereal *, doublereal *);
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extern doublereal dlamch_(char *, ftnlen);
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doublereal deemin;
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integer iwhila, iwhilb;
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doublereal oldemn, safmin;
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extern /* Subroutine */ int xerbla_(char *, integer *, ftnlen);
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extern integer ilaenv_(integer *, char *, char *, integer *, integer *,
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integer *, integer *, ftnlen, ftnlen);
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extern /* Subroutine */ int dlasrt_(char *, integer *, doublereal *,
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integer *, ftnlen);
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/* -- LAPACK computational routine -- */
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/* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
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/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
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/* .. Scalar Arguments .. */
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/* .. */
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/* .. Array Arguments .. */
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/* .. */
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/* ===================================================================== */
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/* .. Parameters .. */
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/* .. */
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/* .. Local Scalars .. */
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/* .. */
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/* .. External Subroutines .. */
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/* .. */
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/* .. External Functions .. */
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/* .. */
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/* .. Intrinsic Functions .. */
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/* .. */
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/* .. Executable Statements .. */
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/* Test the input arguments. */
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/* (in case DLASQ2 is not called by DLASQ1) */
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/* Parameter adjustments */
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--z__;
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/* Function Body */
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*info = 0;
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eps = dlamch_((char *)"Precision", (ftnlen)9);
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safmin = dlamch_((char *)"Safe minimum", (ftnlen)12);
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tol = eps * 100.;
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/* Computing 2nd power */
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d__1 = tol;
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tol2 = d__1 * d__1;
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if (*n < 0) {
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*info = -1;
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xerbla_((char *)"DLASQ2", &c__1, (ftnlen)6);
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return 0;
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} else if (*n == 0) {
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return 0;
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} else if (*n == 1) {
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/* 1-by-1 case. */
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if (z__[1] < 0.) {
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*info = -201;
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xerbla_((char *)"DLASQ2", &c__2, (ftnlen)6);
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}
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return 0;
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} else if (*n == 2) {
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/* 2-by-2 case. */
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if (z__[1] < 0.) {
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*info = -201;
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xerbla_((char *)"DLASQ2", &c__2, (ftnlen)6);
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return 0;
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} else if (z__[2] < 0.) {
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*info = -202;
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xerbla_((char *)"DLASQ2", &c__2, (ftnlen)6);
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return 0;
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} else if (z__[3] < 0.) {
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*info = -203;
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xerbla_((char *)"DLASQ2", &c__2, (ftnlen)6);
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return 0;
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} else if (z__[3] > z__[1]) {
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d__ = z__[3];
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z__[3] = z__[1];
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z__[1] = d__;
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}
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z__[5] = z__[1] + z__[2] + z__[3];
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if (z__[2] > z__[3] * tol2) {
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t = (z__[1] - z__[3] + z__[2]) * .5;
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s = z__[3] * (z__[2] / t);
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if (s <= t) {
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s = z__[3] * (z__[2] / (t * (sqrt(s / t + 1.) + 1.)));
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} else {
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s = z__[3] * (z__[2] / (t + sqrt(t) * sqrt(t + s)));
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}
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t = z__[1] + (s + z__[2]);
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z__[3] *= z__[1] / t;
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z__[1] = t;
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}
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z__[2] = z__[3];
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z__[6] = z__[2] + z__[1];
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return 0;
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}
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/* Check for negative data and compute sums of q's and e's. */
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z__[*n * 2] = 0.;
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emin = z__[2];
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qmax = 0.;
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zmax = 0.;
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d__ = 0.;
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e = 0.;
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i__1 = *n - 1 << 1;
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for (k = 1; k <= i__1; k += 2) {
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if (z__[k] < 0.) {
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*info = -(k + 200);
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xerbla_((char *)"DLASQ2", &c__2, (ftnlen)6);
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return 0;
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} else if (z__[k + 1] < 0.) {
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*info = -(k + 201);
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xerbla_((char *)"DLASQ2", &c__2, (ftnlen)6);
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return 0;
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}
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d__ += z__[k];
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e += z__[k + 1];
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/* Computing MAX */
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d__1 = qmax, d__2 = z__[k];
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qmax = max(d__1,d__2);
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/* Computing MIN */
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d__1 = emin, d__2 = z__[k + 1];
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emin = min(d__1,d__2);
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/* Computing MAX */
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d__1 = max(qmax,zmax), d__2 = z__[k + 1];
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zmax = max(d__1,d__2);
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/* L10: */
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}
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if (z__[(*n << 1) - 1] < 0.) {
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*info = -((*n << 1) + 199);
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xerbla_((char *)"DLASQ2", &c__2, (ftnlen)6);
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return 0;
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}
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d__ += z__[(*n << 1) - 1];
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/* Computing MAX */
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d__1 = qmax, d__2 = z__[(*n << 1) - 1];
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qmax = max(d__1,d__2);
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zmax = max(qmax,zmax);
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/* Check for diagonality. */
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if (e == 0.) {
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i__1 = *n;
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for (k = 2; k <= i__1; ++k) {
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z__[k] = z__[(k << 1) - 1];
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/* L20: */
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}
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dlasrt_((char *)"D", n, &z__[1], &iinfo, (ftnlen)1);
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z__[(*n << 1) - 1] = d__;
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return 0;
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}
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trace = d__ + e;
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/* Check for zero data. */
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if (trace == 0.) {
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z__[(*n << 1) - 1] = 0.;
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return 0;
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}
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/* Check whether the machine is IEEE conformable. */
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ieee = ilaenv_(&c__10, (char *)"DLASQ2", (char *)"N", &c__1, &c__2, &c__3, &c__4, (ftnlen)
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6, (ftnlen)1) == 1;
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/* Rearrange data for locality: Z=(q1,qq1,e1,ee1,q2,qq2,e2,ee2,...). */
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for (k = *n << 1; k >= 2; k += -2) {
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z__[k * 2] = 0.;
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z__[(k << 1) - 1] = z__[k];
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z__[(k << 1) - 2] = 0.;
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z__[(k << 1) - 3] = z__[k - 1];
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/* L30: */
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}
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i0 = 1;
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n0 = *n;
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/* Reverse the qd-array, if warranted. */
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if (z__[(i0 << 2) - 3] * 1.5 < z__[(n0 << 2) - 3]) {
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ipn4 = i0 + n0 << 2;
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i__1 = i0 + n0 - 1 << 1;
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for (i4 = i0 << 2; i4 <= i__1; i4 += 4) {
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temp = z__[i4 - 3];
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z__[i4 - 3] = z__[ipn4 - i4 - 3];
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z__[ipn4 - i4 - 3] = temp;
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temp = z__[i4 - 1];
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z__[i4 - 1] = z__[ipn4 - i4 - 5];
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z__[ipn4 - i4 - 5] = temp;
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/* L40: */
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}
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}
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/* Initial split checking via dqd and Li's test. */
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pp = 0;
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for (k = 1; k <= 2; ++k) {
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d__ = z__[(n0 << 2) + pp - 3];
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i__1 = (i0 << 2) + pp;
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for (i4 = (n0 - 1 << 2) + pp; i4 >= i__1; i4 += -4) {
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if (z__[i4 - 1] <= tol2 * d__) {
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z__[i4 - 1] = -0.;
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d__ = z__[i4 - 3];
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} else {
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d__ = z__[i4 - 3] * (d__ / (d__ + z__[i4 - 1]));
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}
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/* L50: */
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}
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/* dqd maps Z to ZZ plus Li's test. */
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emin = z__[(i0 << 2) + pp + 1];
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d__ = z__[(i0 << 2) + pp - 3];
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i__1 = (n0 - 1 << 2) + pp;
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for (i4 = (i0 << 2) + pp; i4 <= i__1; i4 += 4) {
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z__[i4 - (pp << 1) - 2] = d__ + z__[i4 - 1];
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if (z__[i4 - 1] <= tol2 * d__) {
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z__[i4 - 1] = -0.;
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z__[i4 - (pp << 1) - 2] = d__;
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z__[i4 - (pp << 1)] = 0.;
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d__ = z__[i4 + 1];
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} else if (safmin * z__[i4 + 1] < z__[i4 - (pp << 1) - 2] &&
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safmin * z__[i4 - (pp << 1) - 2] < z__[i4 + 1]) {
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temp = z__[i4 + 1] / z__[i4 - (pp << 1) - 2];
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z__[i4 - (pp << 1)] = z__[i4 - 1] * temp;
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d__ *= temp;
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} else {
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z__[i4 - (pp << 1)] = z__[i4 + 1] * (z__[i4 - 1] / z__[i4 - (
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pp << 1) - 2]);
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d__ = z__[i4 + 1] * (d__ / z__[i4 - (pp << 1) - 2]);
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}
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/* Computing MIN */
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d__1 = emin, d__2 = z__[i4 - (pp << 1)];
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emin = min(d__1,d__2);
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/* L60: */
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}
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z__[(n0 << 2) - pp - 2] = d__;
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/* Now find qmax. */
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qmax = z__[(i0 << 2) - pp - 2];
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i__1 = (n0 << 2) - pp - 2;
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for (i4 = (i0 << 2) - pp + 2; i4 <= i__1; i4 += 4) {
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/* Computing MAX */
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d__1 = qmax, d__2 = z__[i4];
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qmax = max(d__1,d__2);
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/* L70: */
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}
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/* Prepare for the next iteration on K. */
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pp = 1 - pp;
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/* L80: */
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}
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/* Initialise variables to pass to DLASQ3. */
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ttype = 0;
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dmin1 = 0.;
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dmin2 = 0.;
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dn = 0.;
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dn1 = 0.;
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dn2 = 0.;
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g = 0.;
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tau = 0.;
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iter = 2;
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nfail = 0;
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ndiv = n0 - i0 << 1;
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i__1 = *n + 1;
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for (iwhila = 1; iwhila <= i__1; ++iwhila) {
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if (n0 < 1) {
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goto L170;
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}
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/* While array unfinished do */
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/* E(N0) holds the value of SIGMA when submatrix in I0:N0 */
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/* splits from the rest of the array, but is negated. */
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desig = 0.;
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if (n0 == *n) {
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sigma = 0.;
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} else {
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sigma = -z__[(n0 << 2) - 1];
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}
|
|
if (sigma < 0.) {
|
|
*info = 1;
|
|
return 0;
|
|
}
|
|
|
|
/* Find last unreduced submatrix's top index I0, find QMAX and */
|
|
/* EMIN. Find Gershgorin-type bound if Q's much greater than E's. */
|
|
|
|
emax = 0.;
|
|
if (n0 > i0) {
|
|
emin = (d__1 = z__[(n0 << 2) - 5], abs(d__1));
|
|
} else {
|
|
emin = 0.;
|
|
}
|
|
qmin = z__[(n0 << 2) - 3];
|
|
qmax = qmin;
|
|
for (i4 = n0 << 2; i4 >= 8; i4 += -4) {
|
|
if (z__[i4 - 5] <= 0.) {
|
|
goto L100;
|
|
}
|
|
if (qmin >= emax * 4.) {
|
|
/* Computing MIN */
|
|
d__1 = qmin, d__2 = z__[i4 - 3];
|
|
qmin = min(d__1,d__2);
|
|
/* Computing MAX */
|
|
d__1 = emax, d__2 = z__[i4 - 5];
|
|
emax = max(d__1,d__2);
|
|
}
|
|
/* Computing MAX */
|
|
d__1 = qmax, d__2 = z__[i4 - 7] + z__[i4 - 5];
|
|
qmax = max(d__1,d__2);
|
|
/* Computing MIN */
|
|
d__1 = emin, d__2 = z__[i4 - 5];
|
|
emin = min(d__1,d__2);
|
|
/* L90: */
|
|
}
|
|
i4 = 4;
|
|
|
|
L100:
|
|
i0 = i4 / 4;
|
|
pp = 0;
|
|
|
|
if (n0 - i0 > 1) {
|
|
dee = z__[(i0 << 2) - 3];
|
|
deemin = dee;
|
|
kmin = i0;
|
|
i__2 = (n0 << 2) - 3;
|
|
for (i4 = (i0 << 2) + 1; i4 <= i__2; i4 += 4) {
|
|
dee = z__[i4] * (dee / (dee + z__[i4 - 2]));
|
|
if (dee <= deemin) {
|
|
deemin = dee;
|
|
kmin = (i4 + 3) / 4;
|
|
}
|
|
/* L110: */
|
|
}
|
|
if (kmin - i0 << 1 < n0 - kmin && deemin <= z__[(n0 << 2) - 3] *
|
|
.5) {
|
|
ipn4 = i0 + n0 << 2;
|
|
pp = 2;
|
|
i__2 = i0 + n0 - 1 << 1;
|
|
for (i4 = i0 << 2; i4 <= i__2; i4 += 4) {
|
|
temp = z__[i4 - 3];
|
|
z__[i4 - 3] = z__[ipn4 - i4 - 3];
|
|
z__[ipn4 - i4 - 3] = temp;
|
|
temp = z__[i4 - 2];
|
|
z__[i4 - 2] = z__[ipn4 - i4 - 2];
|
|
z__[ipn4 - i4 - 2] = temp;
|
|
temp = z__[i4 - 1];
|
|
z__[i4 - 1] = z__[ipn4 - i4 - 5];
|
|
z__[ipn4 - i4 - 5] = temp;
|
|
temp = z__[i4];
|
|
z__[i4] = z__[ipn4 - i4 - 4];
|
|
z__[ipn4 - i4 - 4] = temp;
|
|
/* L120: */
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Put -(initial shift) into DMIN. */
|
|
|
|
/* Computing MAX */
|
|
d__1 = 0., d__2 = qmin - sqrt(qmin) * 2. * sqrt(emax);
|
|
dmin__ = -max(d__1,d__2);
|
|
|
|
/* Now I0:N0 is unreduced. */
|
|
/* PP = 0 for ping, PP = 1 for pong. */
|
|
/* PP = 2 indicates that flipping was applied to the Z array and */
|
|
/* and that the tests for deflation upon entry in DLASQ3 */
|
|
/* should not be performed. */
|
|
|
|
nbig = (n0 - i0 + 1) * 100;
|
|
i__2 = nbig;
|
|
for (iwhilb = 1; iwhilb <= i__2; ++iwhilb) {
|
|
if (i0 > n0) {
|
|
goto L150;
|
|
}
|
|
|
|
/* While submatrix unfinished take a good dqds step. */
|
|
|
|
dlasq3_(&i0, &n0, &z__[1], &pp, &dmin__, &sigma, &desig, &qmax, &
|
|
nfail, &iter, &ndiv, &ieee, &ttype, &dmin1, &dmin2, &dn, &
|
|
dn1, &dn2, &g, &tau);
|
|
|
|
pp = 1 - pp;
|
|
|
|
/* When EMIN is very small check for splits. */
|
|
|
|
if (pp == 0 && n0 - i0 >= 3) {
|
|
if (z__[n0 * 4] <= tol2 * qmax || z__[(n0 << 2) - 1] <= tol2 *
|
|
sigma) {
|
|
splt = i0 - 1;
|
|
qmax = z__[(i0 << 2) - 3];
|
|
emin = z__[(i0 << 2) - 1];
|
|
oldemn = z__[i0 * 4];
|
|
i__3 = n0 - 3 << 2;
|
|
for (i4 = i0 << 2; i4 <= i__3; i4 += 4) {
|
|
if (z__[i4] <= tol2 * z__[i4 - 3] || z__[i4 - 1] <=
|
|
tol2 * sigma) {
|
|
z__[i4 - 1] = -sigma;
|
|
splt = i4 / 4;
|
|
qmax = 0.;
|
|
emin = z__[i4 + 3];
|
|
oldemn = z__[i4 + 4];
|
|
} else {
|
|
/* Computing MAX */
|
|
d__1 = qmax, d__2 = z__[i4 + 1];
|
|
qmax = max(d__1,d__2);
|
|
/* Computing MIN */
|
|
d__1 = emin, d__2 = z__[i4 - 1];
|
|
emin = min(d__1,d__2);
|
|
/* Computing MIN */
|
|
d__1 = oldemn, d__2 = z__[i4];
|
|
oldemn = min(d__1,d__2);
|
|
}
|
|
/* L130: */
|
|
}
|
|
z__[(n0 << 2) - 1] = emin;
|
|
z__[n0 * 4] = oldemn;
|
|
i0 = splt + 1;
|
|
}
|
|
}
|
|
|
|
/* L140: */
|
|
}
|
|
|
|
*info = 2;
|
|
|
|
/* Maximum number of iterations exceeded, restore the shift */
|
|
/* SIGMA and place the new d's and e's in a qd array. */
|
|
/* This might need to be done for several blocks */
|
|
|
|
i1 = i0;
|
|
n1 = n0;
|
|
L145:
|
|
tempq = z__[(i0 << 2) - 3];
|
|
z__[(i0 << 2) - 3] += sigma;
|
|
i__2 = n0;
|
|
for (k = i0 + 1; k <= i__2; ++k) {
|
|
tempe = z__[(k << 2) - 5];
|
|
z__[(k << 2) - 5] *= tempq / z__[(k << 2) - 7];
|
|
tempq = z__[(k << 2) - 3];
|
|
z__[(k << 2) - 3] = z__[(k << 2) - 3] + sigma + tempe - z__[(k <<
|
|
2) - 5];
|
|
}
|
|
|
|
/* Prepare to do this on the previous block if there is one */
|
|
|
|
if (i1 > 1) {
|
|
n1 = i1 - 1;
|
|
while(i1 >= 2 && z__[(i1 << 2) - 5] >= 0.) {
|
|
--i1;
|
|
}
|
|
sigma = -z__[(n1 << 2) - 1];
|
|
goto L145;
|
|
}
|
|
i__2 = *n;
|
|
for (k = 1; k <= i__2; ++k) {
|
|
z__[(k << 1) - 1] = z__[(k << 2) - 3];
|
|
|
|
/* Only the block 1..N0 is unfinished. The rest of the e's */
|
|
/* must be essentially zero, although sometimes other data */
|
|
/* has been stored in them. */
|
|
|
|
if (k < n0) {
|
|
z__[k * 2] = z__[(k << 2) - 1];
|
|
} else {
|
|
z__[k * 2] = 0.;
|
|
}
|
|
}
|
|
return 0;
|
|
|
|
/* end IWHILB */
|
|
|
|
L150:
|
|
|
|
/* L160: */
|
|
;
|
|
}
|
|
|
|
*info = 3;
|
|
return 0;
|
|
|
|
/* end IWHILA */
|
|
|
|
L170:
|
|
|
|
/* Move q's to the front. */
|
|
|
|
i__1 = *n;
|
|
for (k = 2; k <= i__1; ++k) {
|
|
z__[k] = z__[(k << 2) - 3];
|
|
/* L180: */
|
|
}
|
|
|
|
/* Sort and compute sum of eigenvalues. */
|
|
|
|
dlasrt_((char *)"D", n, &z__[1], &iinfo, (ftnlen)1);
|
|
|
|
e = 0.;
|
|
for (k = *n; k >= 1; --k) {
|
|
e += z__[k];
|
|
/* L190: */
|
|
}
|
|
|
|
/* Store trace, sum(eigenvalues) and information on performance. */
|
|
|
|
z__[(*n << 1) + 1] = trace;
|
|
z__[(*n << 1) + 2] = e;
|
|
z__[(*n << 1) + 3] = (doublereal) iter;
|
|
/* Computing 2nd power */
|
|
i__1 = *n;
|
|
z__[(*n << 1) + 4] = (doublereal) ndiv / (doublereal) (i__1 * i__1);
|
|
z__[(*n << 1) + 5] = nfail * 100. / (doublereal) iter;
|
|
return 0;
|
|
|
|
/* End of DLASQ2 */
|
|
|
|
} /* dlasq2_ */
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|