sget38.c

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/* sget38.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__3 = 3;
static integer c__1 = 1;
static integer c__4 = 4;
static integer c__20 = 20;
static integer c__1200 = 1200;
static integer c__400 = 400;

/* Subroutine */ int sget38_(real *rmax, integer *lmax, integer *ninfo, 
        integer *knt, integer *nin)
{
    /* System generated locals */
    integer i__1, i__2;
    real r__1, r__2;

    /* Builtin functions */
    double sqrt(doublereal);
    integer s_rsle(cilist *), do_lio(integer *, integer *, char *, ftnlen), 
            e_rsle(void);

    /* Local variables */
    integer i__, j, m, n;
    real q[400] /* was [20][20] */, s, t[400]   /* was [20][20] */, v, wi[20],
             wr[20], val[3], eps, sep, sin__, tol, tmp[400]     /* was [20][
            20] */;
    integer ndim, iscl, info, kmin, itmp, ipnt[20];
    real vmax, qsav[400]        /* was [20][20] */, tsav[400]   /* was [20][
            20] */, tnrm, qtmp[400]     /* was [20][20] */, work[1200], stmp, 
            vmul, ttmp[400]     /* was [20][20] */, tsav1[400]  /* was [20][
            20] */;
    extern /* Subroutine */ int sscal_(integer *, real *, real *, integer *);
    real sepin, vimin;
    extern /* Subroutine */ int shst01_(integer *, integer *, integer *, real 
            *, integer *, real *, integer *, real *, integer *, real *, 
            integer *, real *);
    real tolin, vrmin;
    integer iwork[400];
    extern /* Subroutine */ int scopy_(integer *, real *, integer *, real *, 
            integer *);
    real witmp[20], wrtmp[20];
    extern /* Subroutine */ int slabad_(real *, real *);
    integer iselec[20];
    extern doublereal slamch_(char *), slange_(char *, integer *, 
            integer *, real *, integer *, real *);
    extern /* Subroutine */ int sgehrd_(integer *, integer *, integer *, real 
            *, integer *, real *, real *, integer *, integer *);
    logical select[20];
    real bignum;
    extern /* Subroutine */ int slacpy_(char *, integer *, integer *, real *, 
            integer *, real *, integer *), sorghr_(integer *, integer 
            *, integer *, real *, integer *, real *, real *, integer *, 
            integer *), shseqr_(char *, char *, integer *, integer *, integer 
            *, real *, integer *, real *, real *, real *, integer *, real *, 
            integer *, integer *);
    real septmp, smlnum, result[2];
    extern /* Subroutine */ int strsen_(char *, char *, logical *, integer *, 
            real *, integer *, real *, integer *, real *, real *, integer *, 
            real *, real *, real *, integer *, integer *, integer *, integer *
);

    /* Fortran I/O blocks */
    static cilist io___5 = { 0, 0, 0, 0, 0 };
    static cilist io___8 = { 0, 0, 0, 0, 0 };
    static cilist io___11 = { 0, 0, 0, 0, 0 };
    static cilist io___14 = { 0, 0, 0, 0, 0 };



/*  -- LAPACK test routine (version 3.1) -- */
/*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
/*     November 2006 */

/*     .. Scalar Arguments .. */
/*     .. */
/*     .. Array Arguments .. */
/*     .. */

/*  Purpose */
/*  ======= */

/*  SGET38 tests STRSEN, a routine for estimating condition numbers of a */
/*  cluster of eigenvalues and/or its associated right invariant subspace */

/*  The test matrices are read from a file with logical unit number NIN. */

/*  Arguments */
/*  ========== */

/*  RMAX    (output) REAL array, dimension (3) */
/*          Values of the largest test ratios. */
/*          RMAX(1) = largest residuals from SHST01 or comparing */
/*                    different calls to STRSEN */
/*          RMAX(2) = largest error in reciprocal condition */
/*                    numbers taking their conditioning into account */
/*          RMAX(3) = largest error in reciprocal condition */
/*                    numbers not taking their conditioning into */
/*                    account (may be larger than RMAX(2)) */

/*  LMAX    (output) INTEGER array, dimension (3) */
/*          LMAX(i) is example number where largest test ratio */
/*          RMAX(i) is achieved. Also: */
/*          If SGEHRD returns INFO nonzero on example i, LMAX(1)=i */
/*          If SHSEQR returns INFO nonzero on example i, LMAX(2)=i */
/*          If STRSEN returns INFO nonzero on example i, LMAX(3)=i */

/*  NINFO   (output) INTEGER array, dimension (3) */
/*          NINFO(1) = No. of times SGEHRD returned INFO nonzero */
/*          NINFO(2) = No. of times SHSEQR returned INFO nonzero */
/*          NINFO(3) = No. of times STRSEN returned INFO nonzero */

/*  KNT     (output) INTEGER */
/*          Total number of examples tested. */

/*  NIN     (input) INTEGER */
/*          Input logical unit number. */

/*  ===================================================================== */

/*     .. Parameters .. */
/*     .. */
/*     .. Local Scalars .. */
/*     .. */
/*     .. Local Arrays .. */
/*     .. */
/*     .. External Functions .. */
/*     .. */
/*     .. External Subroutines .. */
/*     .. */
/*     .. Intrinsic Functions .. */
/*     .. */
/*     .. Executable Statements .. */

    /* Parameter adjustments */
    --ninfo;
    --lmax;
    --rmax;

    /* Function Body */
    eps = slamch_("P");
    smlnum = slamch_("S") / eps;
    bignum = 1.f / smlnum;
    slabad_(&smlnum, &bignum);

/*     EPSIN = 2**(-24) = precision to which input data computed */

    eps = dmax(eps,5.9605e-8f);
    rmax[1] = 0.f;
    rmax[2] = 0.f;
    rmax[3] = 0.f;
    lmax[1] = 0;
    lmax[2] = 0;
    lmax[3] = 0;
    *knt = 0;
    ninfo[1] = 0;
    ninfo[2] = 0;
    ninfo[3] = 0;

    val[0] = sqrt(smlnum);
    val[1] = 1.f;
    val[2] = sqrt(sqrt(bignum));

/*     Read input data until N=0.  Assume input eigenvalues are sorted */
/*     lexicographically (increasing by real part, then decreasing by */
/*     imaginary part) */

L10:
    io___5.ciunit = *nin;
    s_rsle(&io___5);
    do_lio(&c__3, &c__1, (char *)&n, (ftnlen)sizeof(integer));
    do_lio(&c__3, &c__1, (char *)&ndim, (ftnlen)sizeof(integer));
    e_rsle();
    if (n == 0) {
        return 0;
    }
    io___8.ciunit = *nin;
    s_rsle(&io___8);
    i__1 = ndim;
    for (i__ = 1; i__ <= i__1; ++i__) {
        do_lio(&c__3, &c__1, (char *)&iselec[i__ - 1], (ftnlen)sizeof(integer)
                );
    }
    e_rsle();
    i__1 = n;
    for (i__ = 1; i__ <= i__1; ++i__) {
        io___11.ciunit = *nin;
        s_rsle(&io___11);
        i__2 = n;
        for (j = 1; j <= i__2; ++j) {
            do_lio(&c__4, &c__1, (char *)&tmp[i__ + j * 20 - 21], (ftnlen)
                    sizeof(real));
        }
        e_rsle();
/* L20: */
    }
    io___14.ciunit = *nin;
    s_rsle(&io___14);
    do_lio(&c__4, &c__1, (char *)&sin__, (ftnlen)sizeof(real));
    do_lio(&c__4, &c__1, (char *)&sepin, (ftnlen)sizeof(real));
    e_rsle();

    tnrm = slange_("M", &n, &n, tmp, &c__20, work);
    for (iscl = 1; iscl <= 3; ++iscl) {

/*        Scale input matrix */

        ++(*knt);
        slacpy_("F", &n, &n, tmp, &c__20, t, &c__20);
        vmul = val[iscl - 1];
        i__1 = n;
        for (i__ = 1; i__ <= i__1; ++i__) {
            sscal_(&n, &vmul, &t[i__ * 20 - 20], &c__1);
/* L30: */
        }
        if (tnrm == 0.f) {
            vmul = 1.f;
        }
        slacpy_("F", &n, &n, t, &c__20, tsav, &c__20);

/*        Compute Schur form */

        i__1 = 1200 - n;
        sgehrd_(&n, &c__1, &n, t, &c__20, work, &work[n], &i__1, &info);
        if (info != 0) {
            lmax[1] = *knt;
            ++ninfo[1];
            goto L160;
        }

/*        Generate orthogonal matrix */

        slacpy_("L", &n, &n, t, &c__20, q, &c__20);
        i__1 = 1200 - n;
        sorghr_(&n, &c__1, &n, q, &c__20, work, &work[n], &i__1, &info);

/*        Compute Schur form */

        shseqr_("S", "V", &n, &c__1, &n, t, &c__20, wr, wi, q, &c__20, work, &
                c__1200, &info);
        if (info != 0) {
            lmax[2] = *knt;
            ++ninfo[2];
            goto L160;
        }

/*        Sort, select eigenvalues */

        i__1 = n;
        for (i__ = 1; i__ <= i__1; ++i__) {
            ipnt[i__ - 1] = i__;
            select[i__ - 1] = FALSE_;
/* L40: */
        }
        scopy_(&n, wr, &c__1, wrtmp, &c__1);
        scopy_(&n, wi, &c__1, witmp, &c__1);
        i__1 = n - 1;
        for (i__ = 1; i__ <= i__1; ++i__) {
            kmin = i__;
            vrmin = wrtmp[i__ - 1];
            vimin = witmp[i__ - 1];
            i__2 = n;
            for (j = i__ + 1; j <= i__2; ++j) {
                if (wrtmp[j - 1] < vrmin) {
                    kmin = j;
                    vrmin = wrtmp[j - 1];
                    vimin = witmp[j - 1];
                }
/* L50: */
            }
            wrtmp[kmin - 1] = wrtmp[i__ - 1];
            witmp[kmin - 1] = witmp[i__ - 1];
            wrtmp[i__ - 1] = vrmin;
            witmp[i__ - 1] = vimin;
            itmp = ipnt[i__ - 1];
            ipnt[i__ - 1] = ipnt[kmin - 1];
            ipnt[kmin - 1] = itmp;
/* L60: */
        }
        i__1 = ndim;
        for (i__ = 1; i__ <= i__1; ++i__) {
            select[ipnt[iselec[i__ - 1] - 1] - 1] = TRUE_;
/* L70: */
        }

/*        Compute condition numbers */

        slacpy_("F", &n, &n, q, &c__20, qsav, &c__20);
        slacpy_("F", &n, &n, t, &c__20, tsav1, &c__20);
        strsen_("B", "V", select, &n, t, &c__20, q, &c__20, wrtmp, witmp, &m, 
                &s, &sep, work, &c__1200, iwork, &c__400, &info);
        if (info != 0) {
            lmax[3] = *knt;
            ++ninfo[3];
            goto L160;
        }
        septmp = sep / vmul;
        stmp = s;

/*        Compute residuals */

        shst01_(&n, &c__1, &n, tsav, &c__20, t, &c__20, q, &c__20, work, &
                c__1200, result);
        vmax = dmax(result[0],result[1]);
        if (vmax > rmax[1]) {
            rmax[1] = vmax;
            if (ninfo[1] == 0) {
                lmax[1] = *knt;
            }
        }

/*        Compare condition number for eigenvalue cluster */
/*        taking its condition number into account */

/* Computing MAX */
        r__1 = (real) n * 2.f * eps * tnrm;
        v = dmax(r__1,smlnum);
        if (tnrm == 0.f) {
            v = 1.f;
        }
        if (v > septmp) {
            tol = 1.f;
        } else {
            tol = v / septmp;
        }
        if (v > sepin) {
            tolin = 1.f;
        } else {
            tolin = v / sepin;
        }
/* Computing MAX */
        r__1 = tol, r__2 = smlnum / eps;
        tol = dmax(r__1,r__2);
/* Computing MAX */
        r__1 = tolin, r__2 = smlnum / eps;
        tolin = dmax(r__1,r__2);
        if (eps * (sin__ - tolin) > stmp + tol) {
            vmax = 1.f / eps;
        } else if (sin__ - tolin > stmp + tol) {
            vmax = (sin__ - tolin) / (stmp + tol);
        } else if (sin__ + tolin < eps * (stmp - tol)) {
            vmax = 1.f / eps;
        } else if (sin__ + tolin < stmp - tol) {
            vmax = (stmp - tol) / (sin__ + tolin);
        } else {
            vmax = 1.f;
        }
        if (vmax > rmax[2]) {
            rmax[2] = vmax;
            if (ninfo[2] == 0) {
                lmax[2] = *knt;
            }
        }

/*        Compare condition numbers for invariant subspace */
/*        taking its condition number into account */

        if (v > septmp * stmp) {
            tol = septmp;
        } else {
            tol = v / stmp;
        }
        if (v > sepin * sin__) {
            tolin = sepin;
        } else {
            tolin = v / sin__;
        }
/* Computing MAX */
        r__1 = tol, r__2 = smlnum / eps;
        tol = dmax(r__1,r__2);
/* Computing MAX */
        r__1 = tolin, r__2 = smlnum / eps;
        tolin = dmax(r__1,r__2);
        if (eps * (sepin - tolin) > septmp + tol) {
            vmax = 1.f / eps;
        } else if (sepin - tolin > septmp + tol) {
            vmax = (sepin - tolin) / (septmp + tol);
        } else if (sepin + tolin < eps * (septmp - tol)) {
            vmax = 1.f / eps;
        } else if (sepin + tolin < septmp - tol) {
            vmax = (septmp - tol) / (sepin + tolin);
        } else {
            vmax = 1.f;
        }
        if (vmax > rmax[2]) {
            rmax[2] = vmax;
            if (ninfo[2] == 0) {
                lmax[2] = *knt;
            }
        }

/*        Compare condition number for eigenvalue cluster */
/*        without taking its condition number into account */

        if (sin__ <= (real) (n << 1) * eps && stmp <= (real) (n << 1) * eps) {
            vmax = 1.f;
        } else if (eps * sin__ > stmp) {
            vmax = 1.f / eps;
        } else if (sin__ > stmp) {
            vmax = sin__ / stmp;
        } else if (sin__ < eps * stmp) {
            vmax = 1.f / eps;
        } else if (sin__ < stmp) {
            vmax = stmp / sin__;
        } else {
            vmax = 1.f;
        }
        if (vmax > rmax[3]) {
            rmax[3] = vmax;
            if (ninfo[3] == 0) {
                lmax[3] = *knt;
            }
        }

/*        Compare condition numbers for invariant subspace */
/*        without taking its condition number into account */

        if (sepin <= v && septmp <= v) {
            vmax = 1.f;
        } else if (eps * sepin > septmp) {
            vmax = 1.f / eps;
        } else if (sepin > septmp) {
            vmax = sepin / septmp;
        } else if (sepin < eps * septmp) {
            vmax = 1.f / eps;
        } else if (sepin < septmp) {
            vmax = septmp / sepin;
        } else {
            vmax = 1.f;
        }
        if (vmax > rmax[3]) {
            rmax[3] = vmax;
            if (ninfo[3] == 0) {
                lmax[3] = *knt;
            }
        }

/*        Compute eigenvalue condition number only and compare */
/*        Update Q */

        vmax = 0.f;
        slacpy_("F", &n, &n, tsav1, &c__20, ttmp, &c__20);
        slacpy_("F", &n, &n, qsav, &c__20, qtmp, &c__20);
        septmp = -1.f;
        stmp = -1.f;
        strsen_("E", "V", select, &n, ttmp, &c__20, qtmp, &c__20, wrtmp, 
                witmp, &m, &stmp, &septmp, work, &c__1200, iwork, &c__400, &
                info);
        if (info != 0) {
            lmax[3] = *knt;
            ++ninfo[3];
            goto L160;
        }
        if (s != stmp) {
            vmax = 1.f / eps;
        }
        if (-1.f != septmp) {
            vmax = 1.f / eps;
        }
        i__1 = n;
        for (i__ = 1; i__ <= i__1; ++i__) {
            i__2 = n;
            for (j = 1; j <= i__2; ++j) {
                if (ttmp[i__ + j * 20 - 21] != t[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
                if (qtmp[i__ + j * 20 - 21] != q[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
/* L80: */
            }
/* L90: */
        }

/*        Compute invariant subspace condition number only and compare */
/*        Update Q */

        slacpy_("F", &n, &n, tsav1, &c__20, ttmp, &c__20);
        slacpy_("F", &n, &n, qsav, &c__20, qtmp, &c__20);
        septmp = -1.f;
        stmp = -1.f;
        strsen_("V", "V", select, &n, ttmp, &c__20, qtmp, &c__20, wrtmp, 
                witmp, &m, &stmp, &septmp, work, &c__1200, iwork, &c__400, &
                info);
        if (info != 0) {
            lmax[3] = *knt;
            ++ninfo[3];
            goto L160;
        }
        if (-1.f != stmp) {
            vmax = 1.f / eps;
        }
        if (sep != septmp) {
            vmax = 1.f / eps;
        }
        i__1 = n;
        for (i__ = 1; i__ <= i__1; ++i__) {
            i__2 = n;
            for (j = 1; j <= i__2; ++j) {
                if (ttmp[i__ + j * 20 - 21] != t[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
                if (qtmp[i__ + j * 20 - 21] != q[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
/* L100: */
            }
/* L110: */
        }

/*        Compute eigenvalue condition number only and compare */
/*        Do not update Q */

        slacpy_("F", &n, &n, tsav1, &c__20, ttmp, &c__20);
        slacpy_("F", &n, &n, qsav, &c__20, qtmp, &c__20);
        septmp = -1.f;
        stmp = -1.f;
        strsen_("E", "N", select, &n, ttmp, &c__20, qtmp, &c__20, wrtmp, 
                witmp, &m, &stmp, &septmp, work, &c__1200, iwork, &c__400, &
                info);
        if (info != 0) {
            lmax[3] = *knt;
            ++ninfo[3];
            goto L160;
        }
        if (s != stmp) {
            vmax = 1.f / eps;
        }
        if (-1.f != septmp) {
            vmax = 1.f / eps;
        }
        i__1 = n;
        for (i__ = 1; i__ <= i__1; ++i__) {
            i__2 = n;
            for (j = 1; j <= i__2; ++j) {
                if (ttmp[i__ + j * 20 - 21] != t[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
                if (qtmp[i__ + j * 20 - 21] != qsav[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
/* L120: */
            }
/* L130: */
        }

/*        Compute invariant subspace condition number only and compare */
/*        Do not update Q */

        slacpy_("F", &n, &n, tsav1, &c__20, ttmp, &c__20);
        slacpy_("F", &n, &n, qsav, &c__20, qtmp, &c__20);
        septmp = -1.f;
        stmp = -1.f;
        strsen_("V", "N", select, &n, ttmp, &c__20, qtmp, &c__20, wrtmp, 
                witmp, &m, &stmp, &septmp, work, &c__1200, iwork, &c__400, &
                info);
        if (info != 0) {
            lmax[3] = *knt;
            ++ninfo[3];
            goto L160;
        }
        if (-1.f != stmp) {
            vmax = 1.f / eps;
        }
        if (sep != septmp) {
            vmax = 1.f / eps;
        }
        i__1 = n;
        for (i__ = 1; i__ <= i__1; ++i__) {
            i__2 = n;
            for (j = 1; j <= i__2; ++j) {
                if (ttmp[i__ + j * 20 - 21] != t[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
                if (qtmp[i__ + j * 20 - 21] != qsav[i__ + j * 20 - 21]) {
                    vmax = 1.f / eps;
                }
/* L140: */
            }
/* L150: */
        }
        if (vmax > rmax[1]) {
            rmax[1] = vmax;
            if (ninfo[1] == 0) {
                lmax[1] = *knt;
            }
        }
L160:
        ;
    }
    goto L10;

/*     End of SGET38 */

} /* sget38_ */