zchktb.c

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/* zchktb.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"

/* Common Block Declarations */

struct {
    integer infot, iounit;
    logical ok, lerr;
} infoc_;

#define infoc_1 infoc_

struct {
    char srnamt[32];
} srnamc_;

#define srnamc_1 srnamc_

/* Table of constant values */

static doublecomplex c_b14 = {0.,0.};
static doublecomplex c_b15 = {1.,0.};
static integer c__1 = 1;
static integer c__0 = 0;
static integer c__3 = 3;
static integer c_n1 = -1;
static integer c__6 = 6;
static integer c__4 = 4;
static doublereal c_b90 = 1.;
static integer c__7 = 7;
static integer c__8 = 8;

/* Subroutine */ int zchktb_(logical *dotype, integer *nn, integer *nval, 
        integer *nns, integer *nsval, doublereal *thresh, logical *tsterr, 
        integer *nmax, doublecomplex *ab, doublecomplex *ainv, doublecomplex *
        b, doublecomplex *x, doublecomplex *xact, doublecomplex *work, 
        doublereal *rwork, integer *nout)
{
    /* Initialized data */

    static integer iseedy[4] = { 1988,1989,1990,1991 };
    static char uplos[1*2] = "U" "L";
    static char transs[1*3] = "N" "T" "C";

    /* Format strings */
    static char fmt_9999[] = "(\002 UPLO='\002,a1,\002', TRANS='\002,a1,\002"
            "',                        DIAG='\002,a1,\002', N=\002,i5,\002, K"
            "D=\002,i5,\002, NRHS=\002,i5,\002, type \002,i2,\002, test(\002,"
            "i2,\002)=\002,g12.5)";
    static char fmt_9998[] = "(1x,a,\002( '\002,a1,\002', '\002,a1,\002', "
            "'\002,a1,\002',\002,i5,\002,\002,i5,\002,  ... ), type \002,i2"
            ",\002, test(\002,i2,\002)=\002,g12.5)";
    static char fmt_9997[] = "(1x,a,\002( '\002,a1,\002', '\002,a1,\002', "
            "'\002,a1,\002', '\002,a1,\002',\002,i5,\002,\002,i5,\002, ...  )"
            ",  type \002,i2,\002, test(\002,i1,\002)=\002,g12.5)";

    /* System generated locals */
    address a__1[3], a__2[4];
    integer i__1, i__2, i__3, i__4, i__5, i__6[3], i__7[4];
    char ch__1[3], ch__2[4];

    /* Builtin functions */
    /* Subroutine */ int s_copy(char *, char *, ftnlen, ftnlen), s_cat(char *,
             char **, integer *, integer *, ftnlen);
    integer s_wsfe(cilist *), do_fio(integer *, char *, ftnlen), e_wsfe(void);

    /* Local variables */
    integer i__, j, k, n, kd, ik, in, nk, lda, ldab;
    char diag[1];
    integer imat, info;
    char path[3];
    integer irhs, nrhs;
    char norm[1], uplo[1];
    integer nrun;
    extern /* Subroutine */ int alahd_(integer *, char *);
    integer idiag;
    doublereal scale;
    integer nfail, iseed[4];
    extern logical lsame_(char *, char *);
    doublereal rcond;
    integer nimat;
    doublereal anorm;
    integer itran;
    extern /* Subroutine */ int zget04_(integer *, integer *, doublecomplex *, 
             integer *, doublecomplex *, integer *, doublereal *, doublereal *
), ztbt02_(char *, char *, char *, integer *, integer *, integer *
, doublecomplex *, integer *, doublecomplex *, integer *, 
            doublecomplex *, integer *, doublecomplex *, doublereal *, 
            doublereal *), ztbt03_(char *, char *, 
            char *, integer *, integer *, integer *, doublecomplex *, integer 
            *, doublereal *, doublereal *, doublereal *, doublecomplex *, 
            integer *, doublecomplex *, integer *, doublecomplex *, 
            doublereal *);
    char trans[1];
    integer iuplo, nerrs;
    extern /* Subroutine */ int ztbt05_(char *, char *, char *, integer *, 
            integer *, integer *, doublecomplex *, integer *, doublecomplex *, 
             integer *, doublecomplex *, integer *, doublecomplex *, integer *
, doublereal *, doublereal *, doublereal *), ztbt06_(doublereal *, doublereal *, char *, char *, 
            integer *, integer *, doublecomplex *, integer *, doublereal *, 
            doublereal *), zcopy_(integer *, doublecomplex *, 
            integer *, doublecomplex *, integer *), ztbsv_(char *, char *, 
            char *, integer *, integer *, doublecomplex *, integer *, 
            doublecomplex *, integer *);
    char xtype[1];
    integer nimat2;
    extern /* Subroutine */ int alaerh_(char *, char *, integer *, integer *, 
            char *, integer *, integer *, integer *, integer *, integer *, 
            integer *, integer *, integer *, integer *);
    doublereal rcondc, rcondi;
    extern /* Subroutine */ int alasum_(char *, integer *, integer *, integer 
            *, integer *);
    doublereal rcondo, ainvnm;
    extern doublereal zlantb_(char *, char *, char *, integer *, integer *, 
            doublecomplex *, integer *, doublereal *);
    extern /* Subroutine */ int zlatbs_(char *, char *, char *, char *, 
            integer *, integer *, doublecomplex *, integer *, doublecomplex *, 
             doublereal *, doublereal *, integer *), zlattb_(integer *, char *, char *, char *, integer *, 
            integer *, integer *, doublecomplex *, integer *, doublecomplex *, 
             doublecomplex *, doublereal *, integer *)
            , ztbcon_(char *, char *, char *, integer *, integer *, 
            doublecomplex *, integer *, doublereal *, doublecomplex *, 
            doublereal *, integer *), zlacpy_(char *, 
            integer *, integer *, doublecomplex *, integer *, doublecomplex *, 
             integer *), zlarhs_(char *, char *, char *, char *, 
            integer *, integer *, integer *, integer *, integer *, 
            doublecomplex *, integer *, doublecomplex *, integer *, 
            doublecomplex *, integer *, integer *, integer *), zlaset_(char *, integer *, integer *, 
            doublecomplex *, doublecomplex *, doublecomplex *, integer *);
    extern doublereal zlantr_(char *, char *, char *, integer *, integer *, 
            doublecomplex *, integer *, doublereal *);
    extern /* Subroutine */ int ztbrfs_(char *, char *, char *, integer *, 
            integer *, integer *, doublecomplex *, integer *, doublecomplex *, 
             integer *, doublecomplex *, integer *, doublereal *, doublereal *
, doublecomplex *, doublereal *, integer *);
    doublereal result[8];
    extern /* Subroutine */ int zerrtr_(char *, integer *), ztbtrs_(
            char *, char *, char *, integer *, integer *, integer *, 
            doublecomplex *, integer *, doublecomplex *, integer *, integer *);

    /* Fortran I/O blocks */
    static cilist io___39 = { 0, 0, 0, fmt_9999, 0 };
    static cilist io___41 = { 0, 0, 0, fmt_9998, 0 };
    static cilist io___43 = { 0, 0, 0, fmt_9997, 0 };
    static cilist io___44 = { 0, 0, 0, fmt_9997, 0 };



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

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

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

/*  ZCHKTB tests ZTBTRS, -RFS, and -CON, and ZLATBS. */

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

/*  DOTYPE  (input) LOGICAL array, dimension (NTYPES) */
/*          The matrix types to be used for testing.  Matrices of type j */
/*          (for 1 <= j <= NTYPES) are used for testing if DOTYPE(j) = */
/*          .TRUE.; if DOTYPE(j) = .FALSE., then type j is not used. */

/*  NN      (input) INTEGER */
/*          The number of values of N contained in the vector NVAL. */

/*  NVAL    (input) INTEGER array, dimension (NN) */
/*          The values of the matrix column dimension N. */

/*  NNS     (input) INTEGER */
/*          The number of values of NRHS contained in the vector NSVAL. */

/*  NSVAL   (input) INTEGER array, dimension (NNS) */
/*          The values of the number of right hand sides NRHS. */

/*  THRESH  (input) DOUBLE PRECISION */
/*          The threshold value for the test ratios.  A result is */
/*          included in the output file if RESULT >= THRESH.  To have */
/*          every test ratio printed, use THRESH = 0. */

/*  TSTERR  (input) LOGICAL */
/*          Flag that indicates whether error exits are to be tested. */

/*  NMAX    (input) INTEGER */
/*          The leading dimension of the work arrays. */
/*          NMAX >= the maximum value of N in NVAL. */

/*  AB      (workspace) COMPLEX*16 array, dimension (NMAX*NMAX) */

/*  AINV    (workspace) COMPLEX*16 array, dimension (NMAX*NMAX) */

/*  B       (workspace) COMPLEX*16 array, dimension (NMAX*NSMAX) */
/*          where NSMAX is the largest entry in NSVAL. */

/*  X       (workspace) COMPLEX*16 array, dimension (NMAX*NSMAX) */

/*  XACT    (workspace) COMPLEX*16 array, dimension (NMAX*NSMAX) */

/*  WORK    (workspace) COMPLEX*16 array, dimension */
/*                      (NMAX*max(3,NSMAX)) */

/*  RWORK   (workspace) DOUBLE PRECISION array, dimension */
/*                      (max(NMAX,2*NSMAX)) */

/*  NOUT    (input) INTEGER */
/*          The unit number for output. */

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

/*     .. Parameters .. */
/*     .. */
/*     .. Local Scalars .. */
/*     .. */
/*     .. Local Arrays .. */
/*     .. */
/*     .. External Functions .. */
/*     .. */
/*     .. External Subroutines .. */
/*     .. */
/*     .. Scalars in Common .. */
/*     .. */
/*     .. Common blocks .. */
/*     .. */
/*     .. Intrinsic Functions .. */
/*     .. */
/*     .. Data statements .. */
    /* Parameter adjustments */
    --rwork;
    --work;
    --xact;
    --x;
    --b;
    --ainv;
    --ab;
    --nsval;
    --nval;
    --dotype;

    /* Function Body */
/*     .. */
/*     .. Executable Statements .. */

/*     Initialize constants and the random number seed. */

    s_copy(path, "Zomplex precision", (ftnlen)1, (ftnlen)17);
    s_copy(path + 1, "TB", (ftnlen)2, (ftnlen)2);
    nrun = 0;
    nfail = 0;
    nerrs = 0;
    for (i__ = 1; i__ <= 4; ++i__) {
        iseed[i__ - 1] = iseedy[i__ - 1];
/* L10: */
    }

/*     Test the error exits */

    if (*tsterr) {
        zerrtr_(path, nout);
    }
    infoc_1.infot = 0;

    i__1 = *nn;
    for (in = 1; in <= i__1; ++in) {

/*        Do for each value of N in NVAL */

        n = nval[in];
        lda = max(1,n);
        *(unsigned char *)xtype = 'N';
        nimat = 9;
        nimat2 = 17;
        if (n <= 0) {
            nimat = 1;
            nimat2 = 10;
        }

/* Computing MIN */
        i__2 = n + 1;
        nk = min(i__2,4);
        i__2 = nk;
        for (ik = 1; ik <= i__2; ++ik) {

/*           Do for KD = 0, N, (3N-1)/4, and (N+1)/4. This order makes */
/*           it easier to skip redundant values for small values of N. */

            if (ik == 1) {
                kd = 0;
            } else if (ik == 2) {
                kd = max(n,0);
            } else if (ik == 3) {
                kd = (n * 3 - 1) / 4;
            } else if (ik == 4) {
                kd = (n + 1) / 4;
            }
            ldab = kd + 1;

            i__3 = nimat;
            for (imat = 1; imat <= i__3; ++imat) {

/*              Do the tests only if DOTYPE( IMAT ) is true. */

                if (! dotype[imat]) {
                    goto L90;
                }

                for (iuplo = 1; iuplo <= 2; ++iuplo) {

/*                 Do first for UPLO = 'U', then for UPLO = 'L' */

                    *(unsigned char *)uplo = *(unsigned char *)&uplos[iuplo - 
                            1];

/*                 Call ZLATTB to generate a triangular test matrix. */

                    s_copy(srnamc_1.srnamt, "ZLATTB", (ftnlen)32, (ftnlen)6);
                    zlattb_(&imat, uplo, "No transpose", diag, iseed, &n, &kd, 
                             &ab[1], &ldab, &x[1], &work[1], &rwork[1], &info);

/*                 Set IDIAG = 1 for non-unit matrices, 2 for unit. */

                    if (lsame_(diag, "N")) {
                        idiag = 1;
                    } else {
                        idiag = 2;
                    }

/*                 Form the inverse of A so we can get a good estimate */
/*                 of RCONDC = 1/(norm(A) * norm(inv(A))). */

                    zlaset_("Full", &n, &n, &c_b14, &c_b15, &ainv[1], &lda);
                    if (lsame_(uplo, "U")) {
                        i__4 = n;
                        for (j = 1; j <= i__4; ++j) {
                            ztbsv_(uplo, "No transpose", diag, &j, &kd, &ab[1]
, &ldab, &ainv[(j - 1) * lda + 1], &c__1);
/* L20: */
                        }
                    } else {
                        i__4 = n;
                        for (j = 1; j <= i__4; ++j) {
                            i__5 = n - j + 1;
                            ztbsv_(uplo, "No transpose", diag, &i__5, &kd, &
                                    ab[(j - 1) * ldab + 1], &ldab, &ainv[(j - 
                                    1) * lda + j], &c__1);
/* L30: */
                        }
                    }

/*                 Compute the 1-norm condition number of A. */

                    anorm = zlantb_("1", uplo, diag, &n, &kd, &ab[1], &ldab, &
                            rwork[1]);
                    ainvnm = zlantr_("1", uplo, diag, &n, &n, &ainv[1], &lda, 
                            &rwork[1]);
                    if (anorm <= 0. || ainvnm <= 0.) {
                        rcondo = 1.;
                    } else {
                        rcondo = 1. / anorm / ainvnm;
                    }

/*                 Compute the infinity-norm condition number of A. */

                    anorm = zlantb_("I", uplo, diag, &n, &kd, &ab[1], &ldab, &
                            rwork[1]);
                    ainvnm = zlantr_("I", uplo, diag, &n, &n, &ainv[1], &lda, 
                            &rwork[1]);
                    if (anorm <= 0. || ainvnm <= 0.) {
                        rcondi = 1.;
                    } else {
                        rcondi = 1. / anorm / ainvnm;
                    }

                    i__4 = *nns;
                    for (irhs = 1; irhs <= i__4; ++irhs) {
                        nrhs = nsval[irhs];
                        *(unsigned char *)xtype = 'N';

                        for (itran = 1; itran <= 3; ++itran) {

/*                    Do for op(A) = A, A**T, or A**H. */

                            *(unsigned char *)trans = *(unsigned char *)&
                                    transs[itran - 1];
                            if (itran == 1) {
                                *(unsigned char *)norm = 'O';
                                rcondc = rcondo;
                            } else {
                                *(unsigned char *)norm = 'I';
                                rcondc = rcondi;
                            }

/* +    TEST 1 */
/*                    Solve and compute residual for op(A)*x = b. */

                            s_copy(srnamc_1.srnamt, "ZLARHS", (ftnlen)32, (
                                    ftnlen)6);
                            zlarhs_(path, xtype, uplo, trans, &n, &n, &kd, &
                                    idiag, &nrhs, &ab[1], &ldab, &xact[1], &
                                    lda, &b[1], &lda, iseed, &info);
                            *(unsigned char *)xtype = 'C';
                            zlacpy_("Full", &n, &nrhs, &b[1], &lda, &x[1], &
                                    lda);

                            s_copy(srnamc_1.srnamt, "ZTBTRS", (ftnlen)32, (
                                    ftnlen)6);
                            ztbtrs_(uplo, trans, diag, &n, &kd, &nrhs, &ab[1], 
                                     &ldab, &x[1], &lda, &info);

/*                    Check error code from ZTBTRS. */

                            if (info != 0) {
/* Writing concatenation */
                                i__6[0] = 1, a__1[0] = uplo;
                                i__6[1] = 1, a__1[1] = trans;
                                i__6[2] = 1, a__1[2] = diag;
                                s_cat(ch__1, a__1, i__6, &c__3, (ftnlen)3);
                                alaerh_(path, "ZTBTRS", &info, &c__0, ch__1, &
                                        n, &n, &kd, &kd, &nrhs, &imat, &nfail, 
                                         &nerrs, nout);
                            }

                            ztbt02_(uplo, trans, diag, &n, &kd, &nrhs, &ab[1], 
                                     &ldab, &x[1], &lda, &b[1], &lda, &work[1]
, &rwork[1], result);

/* +    TEST 2 */
/*                    Check solution from generated exact solution. */

                            zget04_(&n, &nrhs, &x[1], &lda, &xact[1], &lda, &
                                    rcondc, &result[1]);

/* +    TESTS 3, 4, and 5 */
/*                    Use iterative refinement to improve the solution */
/*                    and compute error bounds. */

                            s_copy(srnamc_1.srnamt, "ZTBRFS", (ftnlen)32, (
                                    ftnlen)6);
                            ztbrfs_(uplo, trans, diag, &n, &kd, &nrhs, &ab[1], 
                                     &ldab, &b[1], &lda, &x[1], &lda, &rwork[
                                    1], &rwork[nrhs + 1], &work[1], &rwork[(
                                    nrhs << 1) + 1], &info);

/*                    Check error code from ZTBRFS. */

                            if (info != 0) {
/* Writing concatenation */
                                i__6[0] = 1, a__1[0] = uplo;
                                i__6[1] = 1, a__1[1] = trans;
                                i__6[2] = 1, a__1[2] = diag;
                                s_cat(ch__1, a__1, i__6, &c__3, (ftnlen)3);
                                alaerh_(path, "ZTBRFS", &info, &c__0, ch__1, &
                                        n, &n, &kd, &kd, &nrhs, &imat, &nfail, 
                                         &nerrs, nout);
                            }

                            zget04_(&n, &nrhs, &x[1], &lda, &xact[1], &lda, &
                                    rcondc, &result[2]);
                            ztbt05_(uplo, trans, diag, &n, &kd, &nrhs, &ab[1], 
                                     &ldab, &b[1], &lda, &x[1], &lda, &xact[1]
, &lda, &rwork[1], &rwork[nrhs + 1], &
                                    result[3]);

/*                       Print information about the tests that did not */
/*                       pass the threshold. */

                            for (k = 1; k <= 5; ++k) {
                                if (result[k - 1] >= *thresh) {
                                    if (nfail == 0 && nerrs == 0) {
                                        alahd_(nout, path);
                                    }
                                    io___39.ciunit = *nout;
                                    s_wsfe(&io___39);
                                    do_fio(&c__1, uplo, (ftnlen)1);
                                    do_fio(&c__1, trans, (ftnlen)1);
                                    do_fio(&c__1, diag, (ftnlen)1);
                                    do_fio(&c__1, (char *)&n, (ftnlen)sizeof(
                                            integer));
                                    do_fio(&c__1, (char *)&kd, (ftnlen)sizeof(
                                            integer));
                                    do_fio(&c__1, (char *)&nrhs, (ftnlen)
                                            sizeof(integer));
                                    do_fio(&c__1, (char *)&imat, (ftnlen)
                                            sizeof(integer));
                                    do_fio(&c__1, (char *)&k, (ftnlen)sizeof(
                                            integer));
                                    do_fio(&c__1, (char *)&result[k - 1], (
                                            ftnlen)sizeof(doublereal));
                                    e_wsfe();
                                    ++nfail;
                                }
/* L40: */
                            }
                            nrun += 5;
/* L50: */
                        }
/* L60: */
                    }

/* +    TEST 6 */
/*                    Get an estimate of RCOND = 1/CNDNUM. */

                    for (itran = 1; itran <= 2; ++itran) {
                        if (itran == 1) {
                            *(unsigned char *)norm = 'O';
                            rcondc = rcondo;
                        } else {
                            *(unsigned char *)norm = 'I';
                            rcondc = rcondi;
                        }
                        s_copy(srnamc_1.srnamt, "ZTBCON", (ftnlen)32, (ftnlen)
                                6);
                        ztbcon_(norm, uplo, diag, &n, &kd, &ab[1], &ldab, &
                                rcond, &work[1], &rwork[1], &info);

/*                    Check error code from ZTBCON. */

                        if (info != 0) {
/* Writing concatenation */
                            i__6[0] = 1, a__1[0] = norm;
                            i__6[1] = 1, a__1[1] = uplo;
                            i__6[2] = 1, a__1[2] = diag;
                            s_cat(ch__1, a__1, i__6, &c__3, (ftnlen)3);
                            alaerh_(path, "ZTBCON", &info, &c__0, ch__1, &n, &
                                    n, &kd, &kd, &c_n1, &imat, &nfail, &nerrs, 
                                     nout);
                        }

                        ztbt06_(&rcond, &rcondc, uplo, diag, &n, &kd, &ab[1], 
                                &ldab, &rwork[1], &result[5]);

/*                    Print the test ratio if it is .GE. THRESH. */

                        if (result[5] >= *thresh) {
                            if (nfail == 0 && nerrs == 0) {
                                alahd_(nout, path);
                            }
                            io___41.ciunit = *nout;
                            s_wsfe(&io___41);
                            do_fio(&c__1, "ZTBCON", (ftnlen)6);
                            do_fio(&c__1, norm, (ftnlen)1);
                            do_fio(&c__1, uplo, (ftnlen)1);
                            do_fio(&c__1, diag, (ftnlen)1);
                            do_fio(&c__1, (char *)&n, (ftnlen)sizeof(integer))
                                    ;
                            do_fio(&c__1, (char *)&kd, (ftnlen)sizeof(integer)
                                    );
                            do_fio(&c__1, (char *)&imat, (ftnlen)sizeof(
                                    integer));
                            do_fio(&c__1, (char *)&c__6, (ftnlen)sizeof(
                                    integer));
                            do_fio(&c__1, (char *)&result[5], (ftnlen)sizeof(
                                    doublereal));
                            e_wsfe();
                            ++nfail;
                        }
                        ++nrun;
/* L70: */
                    }
/* L80: */
                }
L90:
                ;
            }

/*           Use pathological test matrices to test ZLATBS. */

            i__3 = nimat2;
            for (imat = 10; imat <= i__3; ++imat) {

/*              Do the tests only if DOTYPE( IMAT ) is true. */

                if (! dotype[imat]) {
                    goto L120;
                }

                for (iuplo = 1; iuplo <= 2; ++iuplo) {

/*                 Do first for UPLO = 'U', then for UPLO = 'L' */

                    *(unsigned char *)uplo = *(unsigned char *)&uplos[iuplo - 
                            1];
                    for (itran = 1; itran <= 3; ++itran) {

/*                    Do for op(A) = A, A**T, and A**H. */

                        *(unsigned char *)trans = *(unsigned char *)&transs[
                                itran - 1];

/*                    Call ZLATTB to generate a triangular test matrix. */

                        s_copy(srnamc_1.srnamt, "ZLATTB", (ftnlen)32, (ftnlen)
                                6);
                        zlattb_(&imat, uplo, trans, diag, iseed, &n, &kd, &ab[
                                1], &ldab, &x[1], &work[1], &rwork[1], &info);

/* +    TEST 7 */
/*                    Solve the system op(A)*x = b */

                        s_copy(srnamc_1.srnamt, "ZLATBS", (ftnlen)32, (ftnlen)
                                6);
                        zcopy_(&n, &x[1], &c__1, &b[1], &c__1);
                        zlatbs_(uplo, trans, diag, "N", &n, &kd, &ab[1], &
                                ldab, &b[1], &scale, &rwork[1], &info);

/*                    Check error code from ZLATBS. */

                        if (info != 0) {
/* Writing concatenation */
                            i__7[0] = 1, a__2[0] = uplo;
                            i__7[1] = 1, a__2[1] = trans;
                            i__7[2] = 1, a__2[2] = diag;
                            i__7[3] = 1, a__2[3] = "N";
                            s_cat(ch__2, a__2, i__7, &c__4, (ftnlen)4);
                            alaerh_(path, "ZLATBS", &info, &c__0, ch__2, &n, &
                                    n, &kd, &kd, &c_n1, &imat, &nfail, &nerrs, 
                                     nout);
                        }

                        ztbt03_(uplo, trans, diag, &n, &kd, &c__1, &ab[1], &
                                ldab, &scale, &rwork[1], &c_b90, &b[1], &lda, 
                                &x[1], &lda, &work[1], &result[6]);

/* +    TEST 8 */
/*                    Solve op(A)*x = b again with NORMIN = 'Y'. */

                        zcopy_(&n, &x[1], &c__1, &b[1], &c__1);
                        zlatbs_(uplo, trans, diag, "Y", &n, &kd, &ab[1], &
                                ldab, &b[1], &scale, &rwork[1], &info);

/*                    Check error code from ZLATBS. */

                        if (info != 0) {
/* Writing concatenation */
                            i__7[0] = 1, a__2[0] = uplo;
                            i__7[1] = 1, a__2[1] = trans;
                            i__7[2] = 1, a__2[2] = diag;
                            i__7[3] = 1, a__2[3] = "Y";
                            s_cat(ch__2, a__2, i__7, &c__4, (ftnlen)4);
                            alaerh_(path, "ZLATBS", &info, &c__0, ch__2, &n, &
                                    n, &kd, &kd, &c_n1, &imat, &nfail, &nerrs, 
                                     nout);
                        }

                        ztbt03_(uplo, trans, diag, &n, &kd, &c__1, &ab[1], &
                                ldab, &scale, &rwork[1], &c_b90, &b[1], &lda, 
                                &x[1], &lda, &work[1], &result[7]);

/*                    Print information about the tests that did not pass */
/*                    the threshold. */

                        if (result[6] >= *thresh) {
                            if (nfail == 0 && nerrs == 0) {
                                alahd_(nout, path);
                            }
                            io___43.ciunit = *nout;
                            s_wsfe(&io___43);
                            do_fio(&c__1, "ZLATBS", (ftnlen)6);
                            do_fio(&c__1, uplo, (ftnlen)1);
                            do_fio(&c__1, trans, (ftnlen)1);
                            do_fio(&c__1, diag, (ftnlen)1);
                            do_fio(&c__1, "N", (ftnlen)1);
                            do_fio(&c__1, (char *)&n, (ftnlen)sizeof(integer))
                                    ;
                            do_fio(&c__1, (char *)&kd, (ftnlen)sizeof(integer)
                                    );
                            do_fio(&c__1, (char *)&imat, (ftnlen)sizeof(
                                    integer));
                            do_fio(&c__1, (char *)&c__7, (ftnlen)sizeof(
                                    integer));
                            do_fio(&c__1, (char *)&result[6], (ftnlen)sizeof(
                                    doublereal));
                            e_wsfe();
                            ++nfail;
                        }
                        if (result[7] >= *thresh) {
                            if (nfail == 0 && nerrs == 0) {
                                alahd_(nout, path);
                            }
                            io___44.ciunit = *nout;
                            s_wsfe(&io___44);
                            do_fio(&c__1, "ZLATBS", (ftnlen)6);
                            do_fio(&c__1, uplo, (ftnlen)1);
                            do_fio(&c__1, trans, (ftnlen)1);
                            do_fio(&c__1, diag, (ftnlen)1);
                            do_fio(&c__1, "Y", (ftnlen)1);
                            do_fio(&c__1, (char *)&n, (ftnlen)sizeof(integer))
                                    ;
                            do_fio(&c__1, (char *)&kd, (ftnlen)sizeof(integer)
                                    );
                            do_fio(&c__1, (char *)&imat, (ftnlen)sizeof(
                                    integer));
                            do_fio(&c__1, (char *)&c__8, (ftnlen)sizeof(
                                    integer));
                            do_fio(&c__1, (char *)&result[7], (ftnlen)sizeof(
                                    doublereal));
                            e_wsfe();
                            ++nfail;
                        }
                        nrun += 2;
/* L100: */
                    }
/* L110: */
                }
L120:
                ;
            }
/* L130: */
        }
/* L140: */
    }

/*     Print a summary of the results. */

    alasum_(path, nout, &nfail, &nrun, &nerrs);

    return 0;

/*     End of ZCHKTB */

} /* zchktb_ */