Exemplo n.º 1
0
/* Subroutine */ int cdrvgt_(logical *dotype, integer *nn, integer *nval, 
	integer *nrhs, real *thresh, logical *tsterr, complex *a, complex *af,
	 complex *b, complex *x, complex *xact, complex *work, real *rwork, 
	integer *iwork, integer *nout)
{
    /* Initialized data */

    static integer iseedy[4] = { 0,0,0,1 };
    static char transs[1*3] = "N" "T" "C";

    /* Format strings */
    static char fmt_9999[] = "(1x,a6,\002, N =\002,i5,\002, type \002,i2,"
	    "\002, test \002,i2,\002, ratio = \002,g12.5)";
    static char fmt_9998[] = "(1x,a6,\002, FACT='\002,a1,\002', TRANS='\002,"
	    "a1,\002', N =\002,i5,\002, type \002,i2,\002, test \002,i2,\002,"
	    " ratio = \002,g12.5)";

    /* System generated locals */
    address a__1[2];
    integer i__1, i__2, i__3, i__4, i__5, i__6[2];
    real r__1, r__2;
    char ch__1[2];

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

    /* Local variables */
    static char fact[1];
    static real cond;
    static integer mode, koff, imat, info;
    static char path[3], dist[1], type__[1];
    static integer nrun, i__, j, k, m, n, ifact;
    extern /* Subroutine */ int cget04_(integer *, integer *, complex *, 
	    integer *, complex *, integer *, real *, real *);
    static integer nfail, iseed[4];
    static real z__[3];
    extern /* Subroutine */ int cgtt01_(integer *, complex *, complex *, 
	    complex *, complex *, complex *, complex *, complex *, integer *, 
	    complex *, integer *, real *, real *), cgtt02_(char *, integer *, 
	    integer *, complex *, complex *, complex *, complex *, integer *, 
	    complex *, integer *, real *, real *);
    static real rcond;
    extern /* Subroutine */ int cgtt05_(char *, integer *, integer *, complex 
	    *, complex *, complex *, complex *, integer *, complex *, integer 
	    *, complex *, integer *, real *, real *, real *);
    static integer nimat;
    extern doublereal sget06_(real *, real *);
    static real anorm;
    static integer itran;
    extern /* Subroutine */ int ccopy_(integer *, complex *, integer *, 
	    complex *, integer *), cgtsv_(integer *, integer *, complex *, 
	    complex *, complex *, complex *, integer *, integer *);
    static char trans[1];
    static integer izero, nerrs, k1;
    static logical zerot;
    extern /* Subroutine */ int clatb4_(char *, integer *, integer *, integer 
	    *, char *, integer *, integer *, real *, integer *, real *, char *
	    ), aladhd_(integer *, char *);
    static integer in, kl;
    extern /* Subroutine */ int alaerh_(char *, char *, integer *, integer *, 
	    char *, integer *, integer *, integer *, integer *, integer *, 
	    integer *, integer *, integer *, integer *);
    static integer ku, ix, nt;
    extern /* Subroutine */ int clagtm_(char *, integer *, integer *, real *, 
	    complex *, complex *, complex *, complex *, integer *, real *, 
	    complex *, integer *);
    static real rcondc;
    extern doublereal clangt_(char *, integer *, complex *, complex *, 
	    complex *);
    extern /* Subroutine */ int csscal_(integer *, real *, complex *, integer 
	    *), clacpy_(char *, integer *, integer *, complex *, integer *, 
	    complex *, integer *), claset_(char *, integer *, integer 
	    *, complex *, complex *, complex *, integer *);
    static real rcondi;
    extern /* Subroutine */ int alasvm_(char *, integer *, integer *, integer 
	    *, integer *);
    static real rcondo, anormi;
    extern /* Subroutine */ int clarnv_(integer *, integer *, integer *, 
	    complex *), clatms_(integer *, integer *, char *, integer *, char 
	    *, real *, integer *, real *, real *, integer *, integer *, char *
	    , complex *, integer *, complex *, integer *);
    static real ainvnm;
    extern /* Subroutine */ int cgttrf_(integer *, complex *, complex *, 
	    complex *, complex *, integer *, integer *);
    static logical trfcon;
    static real anormo;
    extern doublereal scasum_(integer *, complex *, integer *);
    extern /* Subroutine */ int cgttrs_(char *, integer *, integer *, complex 
	    *, complex *, complex *, complex *, integer *, complex *, integer 
	    *, integer *), cerrvx_(char *, integer *);
    static real result[6];
    extern /* Subroutine */ int cgtsvx_(char *, char *, integer *, integer *, 
	    complex *, complex *, complex *, complex *, complex *, complex *, 
	    complex *, integer *, complex *, integer *, complex *, integer *, 
	    real *, real *, real *, complex *, real *, integer *);
    static integer lda;

    /* Fortran I/O blocks */
    static cilist io___42 = { 0, 0, 0, fmt_9999, 0 };
    static cilist io___46 = { 0, 0, 0, fmt_9998, 0 };
    static cilist io___47 = { 0, 0, 0, fmt_9998, 0 };



/*  -- LAPACK test routine (version 3.0) --   
       Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   
       Courant Institute, Argonne National Lab, and Rice University   
       September 30, 1994   


    Purpose   
    =======   

    CDRVGT tests CGTSV and -SVX.   

    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 dimension N.   

    THRESH  (input) REAL   
            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.   

    A       (workspace) COMPLEX array, dimension (NMAX*4)   

    AF      (workspace) COMPLEX array, dimension (NMAX*4)   

    B       (workspace) COMPLEX array, dimension (NMAX*NRHS)   

    X       (workspace) COMPLEX array, dimension (NMAX*NRHS)   

    XACT    (workspace) COMPLEX array, dimension (NMAX*NRHS)   

    WORK    (workspace) COMPLEX array, dimension   
                        (NMAX*max(3,NRHS))   

    RWORK   (workspace) REAL array, dimension (NMAX+2*NRHS)   

    IWORK   (workspace) INTEGER array, dimension (2*NMAX)   

    NOUT    (input) INTEGER   
            The unit number for output.   

    =====================================================================   

       Parameter adjustments */
    --iwork;
    --rwork;
    --work;
    --xact;
    --x;
    --b;
    --af;
    --a;
    --nval;
    --dotype;

    /* Function Body */

    s_copy(path, "Complex precision", (ftnlen)1, (ftnlen)17);
    s_copy(path + 1, "GT", (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) {
	cerrvx_(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];
/* Computing MAX */
	i__2 = n - 1;
	m = max(i__2,0);
	lda = max(1,n);
	nimat = 12;
	if (n <= 0) {
	    nimat = 1;
	}

	i__2 = nimat;
	for (imat = 1; imat <= i__2; ++imat) {

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

	    if (! dotype[imat]) {
		goto L130;
	    }

/*           Set up parameters with CLATB4. */

	    clatb4_(path, &imat, &n, &n, type__, &kl, &ku, &anorm, &mode, &
		    cond, dist);

	    zerot = imat >= 8 && imat <= 10;
	    if (imat <= 6) {

/*              Types 1-6:  generate matrices of known condition number.   

   Computing MAX */
		i__3 = 2 - ku, i__4 = 3 - max(1,n);
		koff = max(i__3,i__4);
		s_copy(srnamc_1.srnamt, "CLATMS", (ftnlen)6, (ftnlen)6);
		clatms_(&n, &n, dist, iseed, type__, &rwork[1], &mode, &cond, 
			&anorm, &kl, &ku, "Z", &af[koff], &c__3, &work[1], &
			info);

/*              Check the error code from CLATMS. */

		if (info != 0) {
		    alaerh_(path, "CLATMS", &info, &c__0, " ", &n, &n, &kl, &
			    ku, &c_n1, &imat, &nfail, &nerrs, nout);
		    goto L130;
		}
		izero = 0;

		if (n > 1) {
		    i__3 = n - 1;
		    ccopy_(&i__3, &af[4], &c__3, &a[1], &c__1);
		    i__3 = n - 1;
		    ccopy_(&i__3, &af[3], &c__3, &a[n + m + 1], &c__1);
		}
		ccopy_(&n, &af[2], &c__3, &a[m + 1], &c__1);
	    } else {

/*              Types 7-12:  generate tridiagonal matrices with   
                unknown condition numbers. */

		if (! zerot || ! dotype[7]) {

/*                 Generate a matrix with elements from [-1,1]. */

		    i__3 = n + (m << 1);
		    clarnv_(&c__2, iseed, &i__3, &a[1]);
		    if (anorm != 1.f) {
			i__3 = n + (m << 1);
			csscal_(&i__3, &anorm, &a[1], &c__1);
		    }
		} else if (izero > 0) {

/*                 Reuse the last matrix by copying back the zeroed out   
                   elements. */

		    if (izero == 1) {
			i__3 = n;
			a[i__3].r = z__[1], a[i__3].i = 0.f;
			if (n > 1) {
			    a[1].r = z__[2], a[1].i = 0.f;
			}
		    } else if (izero == n) {
			i__3 = n * 3 - 2;
			a[i__3].r = z__[0], a[i__3].i = 0.f;
			i__3 = (n << 1) - 1;
			a[i__3].r = z__[1], a[i__3].i = 0.f;
		    } else {
			i__3 = (n << 1) - 2 + izero;
			a[i__3].r = z__[0], a[i__3].i = 0.f;
			i__3 = n - 1 + izero;
			a[i__3].r = z__[1], a[i__3].i = 0.f;
			i__3 = izero;
			a[i__3].r = z__[2], a[i__3].i = 0.f;
		    }
		}

/*              If IMAT > 7, set one column of the matrix to 0. */

		if (! zerot) {
		    izero = 0;
		} else if (imat == 8) {
		    izero = 1;
		    i__3 = n;
		    z__[1] = a[i__3].r;
		    i__3 = n;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		    if (n > 1) {
			z__[2] = a[1].r;
			a[1].r = 0.f, a[1].i = 0.f;
		    }
		} else if (imat == 9) {
		    izero = n;
		    i__3 = n * 3 - 2;
		    z__[0] = a[i__3].r;
		    i__3 = (n << 1) - 1;
		    z__[1] = a[i__3].r;
		    i__3 = n * 3 - 2;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		    i__3 = (n << 1) - 1;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		} else {
		    izero = (n + 1) / 2;
		    i__3 = n - 1;
		    for (i__ = izero; i__ <= i__3; ++i__) {
			i__4 = (n << 1) - 2 + i__;
			a[i__4].r = 0.f, a[i__4].i = 0.f;
			i__4 = n - 1 + i__;
			a[i__4].r = 0.f, a[i__4].i = 0.f;
			i__4 = i__;
			a[i__4].r = 0.f, a[i__4].i = 0.f;
/* L20: */
		    }
		    i__3 = n * 3 - 2;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		    i__3 = (n << 1) - 1;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		}
	    }

	    for (ifact = 1; ifact <= 2; ++ifact) {
		if (ifact == 1) {
		    *(unsigned char *)fact = 'F';
		} else {
		    *(unsigned char *)fact = 'N';
		}

/*              Compute the condition number for comparison with   
                the value returned by CGTSVX. */

		if (zerot) {
		    if (ifact == 1) {
			goto L120;
		    }
		    rcondo = 0.f;
		    rcondi = 0.f;

		} else if (ifact == 1) {
		    i__3 = n + (m << 1);
		    ccopy_(&i__3, &a[1], &c__1, &af[1], &c__1);

/*                 Compute the 1-norm and infinity-norm of A. */

		    anormo = clangt_("1", &n, &a[1], &a[m + 1], &a[n + m + 1]);
		    anormi = clangt_("I", &n, &a[1], &a[m + 1], &a[n + m + 1]);

/*                 Factor the matrix A. */

		    cgttrf_(&n, &af[1], &af[m + 1], &af[n + m + 1], &af[n + (
			    m << 1) + 1], &iwork[1], &info);

/*                 Use CGTTRS to solve for one column at a time of   
                   inv(A), computing the maximum column sum as we go. */

		    ainvnm = 0.f;
		    i__3 = n;
		    for (i__ = 1; i__ <= i__3; ++i__) {
			i__4 = n;
			for (j = 1; j <= i__4; ++j) {
			    i__5 = j;
			    x[i__5].r = 0.f, x[i__5].i = 0.f;
/* L30: */
			}
			i__4 = i__;
			x[i__4].r = 1.f, x[i__4].i = 0.f;
			cgttrs_("No transpose", &n, &c__1, &af[1], &af[m + 1],
				 &af[n + m + 1], &af[n + (m << 1) + 1], &
				iwork[1], &x[1], &lda, &info);
/* Computing MAX */
			r__1 = ainvnm, r__2 = scasum_(&n, &x[1], &c__1);
			ainvnm = dmax(r__1,r__2);
/* L40: */
		    }

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

		    if (anormo <= 0.f || ainvnm <= 0.f) {
			rcondo = 1.f;
		    } else {
			rcondo = 1.f / anormo / ainvnm;
		    }

/*                 Use CGTTRS to solve for one column at a time of   
                   inv(A'), computing the maximum column sum as we go. */

		    ainvnm = 0.f;
		    i__3 = n;
		    for (i__ = 1; i__ <= i__3; ++i__) {
			i__4 = n;
			for (j = 1; j <= i__4; ++j) {
			    i__5 = j;
			    x[i__5].r = 0.f, x[i__5].i = 0.f;
/* L50: */
			}
			i__4 = i__;
			x[i__4].r = 1.f, x[i__4].i = 0.f;
			cgttrs_("Conjugate transpose", &n, &c__1, &af[1], &af[
				m + 1], &af[n + m + 1], &af[n + (m << 1) + 1],
				 &iwork[1], &x[1], &lda, &info);
/* Computing MAX */
			r__1 = ainvnm, r__2 = scasum_(&n, &x[1], &c__1);
			ainvnm = dmax(r__1,r__2);
/* L60: */
		    }

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

		    if (anormi <= 0.f || ainvnm <= 0.f) {
			rcondi = 1.f;
		    } else {
			rcondi = 1.f / anormi / ainvnm;
		    }
		}

		for (itran = 1; itran <= 3; ++itran) {
		    *(unsigned char *)trans = *(unsigned char *)&transs[itran 
			    - 1];
		    if (itran == 1) {
			rcondc = rcondo;
		    } else {
			rcondc = rcondi;
		    }

/*                 Generate NRHS random solution vectors. */

		    ix = 1;
		    i__3 = *nrhs;
		    for (j = 1; j <= i__3; ++j) {
			clarnv_(&c__2, iseed, &n, &xact[ix]);
			ix += lda;
/* L70: */
		    }

/*                 Set the right hand side. */

		    clagtm_(trans, &n, nrhs, &c_b43, &a[1], &a[m + 1], &a[n + 
			    m + 1], &xact[1], &lda, &c_b44, &b[1], &lda);

		    if (ifact == 2 && itran == 1) {

/*                    --- Test CGTSV  ---   

                      Solve the system using Gaussian elimination with   
                      partial pivoting. */

			i__3 = n + (m << 1);
			ccopy_(&i__3, &a[1], &c__1, &af[1], &c__1);
			clacpy_("Full", &n, nrhs, &b[1], &lda, &x[1], &lda);

			s_copy(srnamc_1.srnamt, "CGTSV ", (ftnlen)6, (ftnlen)
				6);
			cgtsv_(&n, nrhs, &af[1], &af[m + 1], &af[n + m + 1], &
				x[1], &lda, &info);

/*                    Check error code from CGTSV . */

			if (info != izero) {
			    alaerh_(path, "CGTSV ", &info, &izero, " ", &n, &
				    n, &c__1, &c__1, nrhs, &imat, &nfail, &
				    nerrs, nout);
			}
			nt = 1;
			if (izero == 0) {

/*                       Check residual of computed solution. */

			    clacpy_("Full", &n, nrhs, &b[1], &lda, &work[1], &
				    lda);
			    cgtt02_(trans, &n, nrhs, &a[1], &a[m + 1], &a[n + 
				    m + 1], &x[1], &lda, &work[1], &lda, &
				    rwork[1], &result[1]);

/*                       Check solution from generated exact solution. */

			    cget04_(&n, nrhs, &x[1], &lda, &xact[1], &lda, &
				    rcondc, &result[2]);
			    nt = 3;
			}

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

			i__3 = nt;
			for (k = 2; k <= i__3; ++k) {
			    if (result[k - 1] >= *thresh) {
				if (nfail == 0 && nerrs == 0) {
				    aladhd_(nout, path);
				}
				io___42.ciunit = *nout;
				s_wsfe(&io___42);
				do_fio(&c__1, "CGTSV ", (ftnlen)6);
				do_fio(&c__1, (char *)&n, (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(real));
				e_wsfe();
				++nfail;
			    }
/* L80: */
			}
			nrun = nrun + nt - 1;
		    }

/*                 --- Test CGTSVX --- */

		    if (ifact > 1) {

/*                    Initialize AF to zero. */

			i__3 = n * 3 - 2;
			for (i__ = 1; i__ <= i__3; ++i__) {
			    i__4 = i__;
			    af[i__4].r = 0.f, af[i__4].i = 0.f;
/* L90: */
			}
		    }
		    claset_("Full", &n, nrhs, &c_b65, &c_b65, &x[1], &lda);

/*                 Solve the system and compute the condition number and   
                   error bounds using CGTSVX. */

		    s_copy(srnamc_1.srnamt, "CGTSVX", (ftnlen)6, (ftnlen)6);
		    cgtsvx_(fact, trans, &n, nrhs, &a[1], &a[m + 1], &a[n + m 
			    + 1], &af[1], &af[m + 1], &af[n + m + 1], &af[n + 
			    (m << 1) + 1], &iwork[1], &b[1], &lda, &x[1], &
			    lda, &rcond, &rwork[1], &rwork[*nrhs + 1], &work[
			    1], &rwork[(*nrhs << 1) + 1], &info);

/*                 Check the error code from CGTSVX. */

		    if (info != izero) {
/* Writing concatenation */
			i__6[0] = 1, a__1[0] = fact;
			i__6[1] = 1, a__1[1] = trans;
			s_cat(ch__1, a__1, i__6, &c__2, (ftnlen)2);
			alaerh_(path, "CGTSVX", &info, &izero, ch__1, &n, &n, 
				&c__1, &c__1, nrhs, &imat, &nfail, &nerrs, 
				nout);
		    }

		    if (ifact >= 2) {

/*                    Reconstruct matrix from factors and compute   
                      residual. */

			cgtt01_(&n, &a[1], &a[m + 1], &a[n + m + 1], &af[1], &
				af[m + 1], &af[n + m + 1], &af[n + (m << 1) + 
				1], &iwork[1], &work[1], &lda, &rwork[1], 
				result);
			k1 = 1;
		    } else {
			k1 = 2;
		    }

		    if (info == 0) {
			trfcon = FALSE_;

/*                    Check residual of computed solution. */

			clacpy_("Full", &n, nrhs, &b[1], &lda, &work[1], &lda);
			cgtt02_(trans, &n, nrhs, &a[1], &a[m + 1], &a[n + m + 
				1], &x[1], &lda, &work[1], &lda, &rwork[1], &
				result[1]);

/*                    Check solution from generated exact solution. */

			cget04_(&n, nrhs, &x[1], &lda, &xact[1], &lda, &
				rcondc, &result[2]);

/*                    Check the error bounds from iterative refinement. */

			cgtt05_(trans, &n, nrhs, &a[1], &a[m + 1], &a[n + m + 
				1], &b[1], &lda, &x[1], &lda, &xact[1], &lda, 
				&rwork[1], &rwork[*nrhs + 1], &result[3]);
			nt = 5;
		    }

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

		    i__3 = nt;
		    for (k = k1; k <= i__3; ++k) {
			if (result[k - 1] >= *thresh) {
			    if (nfail == 0 && nerrs == 0) {
				aladhd_(nout, path);
			    }
			    io___46.ciunit = *nout;
			    s_wsfe(&io___46);
			    do_fio(&c__1, "CGTSVX", (ftnlen)6);
			    do_fio(&c__1, fact, (ftnlen)1);
			    do_fio(&c__1, trans, (ftnlen)1);
			    do_fio(&c__1, (char *)&n, (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(real));
			    e_wsfe();
			    ++nfail;
			}
/* L100: */
		    }

/*                 Check the reciprocal of the condition number. */

		    result[5] = sget06_(&rcond, &rcondc);
		    if (result[5] >= *thresh) {
			if (nfail == 0 && nerrs == 0) {
			    aladhd_(nout, path);
			}
			io___47.ciunit = *nout;
			s_wsfe(&io___47);
			do_fio(&c__1, "CGTSVX", (ftnlen)6);
			do_fio(&c__1, fact, (ftnlen)1);
			do_fio(&c__1, trans, (ftnlen)1);
			do_fio(&c__1, (char *)&n, (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(
				real));
			e_wsfe();
			++nfail;
		    }
		    nrun = nrun + nt - k1 + 2;

/* L110: */
		}
L120:
		;
	    }
L130:
	    ;
	}
/* L140: */
    }

/*     Print a summary of the results. */

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

    return 0;

/*     End of CDRVGT */

} /* cdrvgt_ */
Exemplo n.º 2
0
/* Subroutine */ int cchkgt_(logical *dotype, integer *nn, integer *nval, 
	integer *nns, integer *nsval, real *thresh, logical *tsterr, complex *
	a, complex *af, complex *b, complex *x, complex *xact, complex *work, 
	real *rwork, integer *iwork, integer *nout)
{
    /* Initialized data */

    static integer iseedy[4] = { 0,0,0,1 };
    static char transs[1*3] = "N" "T" "C";

    /* Format strings */
    static char fmt_9999[] = "(12x,\002N =\002,i5,\002,\002,10x,\002 type"
	    " \002,i2,\002, test(\002,i2,\002) = \002,g12.5)";
    static char fmt_9997[] = "(\002 NORM ='\002,a1,\002', N =\002,i5,\002"
	    ",\002,10x,\002 type \002,i2,\002, test(\002,i2,\002) = \002,g12."
	    "5)";
    static char fmt_9998[] = "(\002 TRANS='\002,a1,\002', N =\002,i5,\002, N"
	    "RHS=\002,i3,\002, type \002,i2,\002, test(\002,i2,\002) = \002,g"
	    "12.5)";

    /* System generated locals */
    integer i__1, i__2, i__3, i__4, i__5;
    real r__1, r__2;

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

    /* Local variables */
    static real cond;
    static integer mode, koff, imat, info;
    static char path[3], dist[1];
    static integer irhs, nrhs;
    static char norm[1], type__[1];
    static integer nrun, i__, j, k;
    extern /* Subroutine */ int alahd_(integer *, char *);
    static integer m, n;
    extern /* Subroutine */ int cget04_(integer *, integer *, complex *, 
	    integer *, complex *, integer *, real *, real *);
    static integer nfail, iseed[4];
    static complex z__[3];
    extern /* Subroutine */ int cgtt01_(integer *, complex *, complex *, 
	    complex *, complex *, complex *, complex *, complex *, integer *, 
	    complex *, integer *, real *, real *), cgtt02_(char *, integer *, 
	    integer *, complex *, complex *, complex *, complex *, integer *, 
	    complex *, integer *, real *, real *);
    static real rcond;
    extern /* Subroutine */ int cgtt05_(char *, integer *, integer *, complex 
	    *, complex *, complex *, complex *, integer *, complex *, integer 
	    *, complex *, integer *, real *, real *, real *);
    static integer nimat;
    extern doublereal sget06_(real *, real *);
    static real anorm;
    static integer itran;
    extern /* Subroutine */ int ccopy_(integer *, complex *, integer *, 
	    complex *, integer *);
    static char trans[1];
    static integer izero, nerrs;
    static logical zerot;
    extern /* Subroutine */ int clatb4_(char *, integer *, integer *, integer 
	    *, char *, integer *, integer *, real *, integer *, real *, char *
	    );
    static integer in, kl;
    extern /* Subroutine */ int alaerh_(char *, char *, integer *, integer *, 
	    char *, integer *, integer *, integer *, integer *, integer *, 
	    integer *, integer *, integer *, integer *);
    static integer ku, ix;
    extern /* Subroutine */ int cerrge_(char *, integer *);
    static real rcondc;
    extern doublereal clangt_(char *, integer *, complex *, complex *, 
	    complex *);
    extern /* Subroutine */ int clagtm_(char *, integer *, integer *, real *, 
	    complex *, complex *, complex *, complex *, integer *, real *, 
	    complex *, integer *), clacpy_(char *, integer *, integer 
	    *, complex *, integer *, complex *, integer *), csscal_(
	    integer *, real *, complex *, integer *), cgtcon_(char *, integer 
	    *, complex *, complex *, complex *, complex *, integer *, real *, 
	    real *, complex *, integer *);
    static real rcondi;
    extern /* Subroutine */ int alasum_(char *, integer *, integer *, integer 
	    *, integer *);
    static real rcondo;
    extern /* Subroutine */ int clarnv_(integer *, integer *, integer *, 
	    complex *), clatms_(integer *, integer *, char *, integer *, char 
	    *, real *, integer *, real *, real *, integer *, integer *, char *
	    , complex *, integer *, complex *, integer *);
    static real ainvnm;
    extern /* Subroutine */ int cgtrfs_(char *, integer *, integer *, complex 
	    *, complex *, complex *, complex *, complex *, complex *, complex 
	    *, integer *, complex *, integer *, complex *, integer *, real *, 
	    real *, complex *, real *, integer *), cgttrf_(integer *, 
	    complex *, complex *, complex *, complex *, integer *, integer *);
    static logical trfcon;
    extern doublereal scasum_(integer *, complex *, integer *);
    extern /* Subroutine */ int cgttrs_(char *, integer *, integer *, complex 
	    *, complex *, complex *, complex *, integer *, complex *, integer 
	    *, integer *);
    static real result[7];
    static integer lda;

    /* Fortran I/O blocks */
    static cilist io___29 = { 0, 0, 0, fmt_9999, 0 };
    static cilist io___39 = { 0, 0, 0, fmt_9997, 0 };
    static cilist io___44 = { 0, 0, 0, fmt_9998, 0 };



/*  -- LAPACK test routine (version 3.0) --   
       Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   
       Courant Institute, Argonne National Lab, and Rice University   
       June 30, 1999   


    Purpose   
    =======   

    CCHKGT tests CGTTRF, -TRS, -RFS, and -CON   

    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 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) REAL   
            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.   

    A       (workspace) COMPLEX array, dimension (NMAX*4)   

    AF      (workspace) COMPLEX array, dimension (NMAX*4)   

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

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

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

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

    RWORK   (workspace) REAL array, dimension   
                        (max(NMAX)+2*NSMAX)   

    IWORK   (workspace) INTEGER array, dimension (NMAX)   

    NOUT    (input) INTEGER   
            The unit number for output.   

    =====================================================================   

       Parameter adjustments */
    --iwork;
    --rwork;
    --work;
    --xact;
    --x;
    --b;
    --af;
    --a;
    --nsval;
    --nval;
    --dotype;

    /* Function Body */

    s_copy(path, "Complex precision", (ftnlen)1, (ftnlen)17);
    s_copy(path + 1, "GT", (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) {
	cerrge_(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];
/* Computing MAX */
	i__2 = n - 1;
	m = max(i__2,0);
	lda = max(1,n);
	nimat = 12;
	if (n <= 0) {
	    nimat = 1;
	}

	i__2 = nimat;
	for (imat = 1; imat <= i__2; ++imat) {

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

	    if (! dotype[imat]) {
		goto L100;
	    }

/*           Set up parameters with CLATB4. */

	    clatb4_(path, &imat, &n, &n, type__, &kl, &ku, &anorm, &mode, &
		    cond, dist);

	    zerot = imat >= 8 && imat <= 10;
	    if (imat <= 6) {

/*              Types 1-6:  generate matrices of known condition number.   

   Computing MAX */
		i__3 = 2 - ku, i__4 = 3 - max(1,n);
		koff = max(i__3,i__4);
		s_copy(srnamc_1.srnamt, "CLATMS", (ftnlen)6, (ftnlen)6);
		clatms_(&n, &n, dist, iseed, type__, &rwork[1], &mode, &cond, 
			&anorm, &kl, &ku, "Z", &af[koff], &c__3, &work[1], &
			info);

/*              Check the error code from CLATMS. */

		if (info != 0) {
		    alaerh_(path, "CLATMS", &info, &c__0, " ", &n, &n, &kl, &
			    ku, &c_n1, &imat, &nfail, &nerrs, nout);
		    goto L100;
		}
		izero = 0;

		if (n > 1) {
		    i__3 = n - 1;
		    ccopy_(&i__3, &af[4], &c__3, &a[1], &c__1);
		    i__3 = n - 1;
		    ccopy_(&i__3, &af[3], &c__3, &a[n + m + 1], &c__1);
		}
		ccopy_(&n, &af[2], &c__3, &a[m + 1], &c__1);
	    } else {

/*              Types 7-12:  generate tridiagonal matrices with   
                unknown condition numbers. */

		if (! zerot || ! dotype[7]) {

/*                 Generate a matrix with elements whose real and   
                   imaginary parts are from [-1,1]. */

		    i__3 = n + (m << 1);
		    clarnv_(&c__2, iseed, &i__3, &a[1]);
		    if (anorm != 1.f) {
			i__3 = n + (m << 1);
			csscal_(&i__3, &anorm, &a[1], &c__1);
		    }
		} else if (izero > 0) {

/*                 Reuse the last matrix by copying back the zeroed out   
                   elements. */

		    if (izero == 1) {
			i__3 = n;
			a[i__3].r = z__[1].r, a[i__3].i = z__[1].i;
			if (n > 1) {
			    a[1].r = z__[2].r, a[1].i = z__[2].i;
			}
		    } else if (izero == n) {
			i__3 = n * 3 - 2;
			a[i__3].r = z__[0].r, a[i__3].i = z__[0].i;
			i__3 = (n << 1) - 1;
			a[i__3].r = z__[1].r, a[i__3].i = z__[1].i;
		    } else {
			i__3 = (n << 1) - 2 + izero;
			a[i__3].r = z__[0].r, a[i__3].i = z__[0].i;
			i__3 = n - 1 + izero;
			a[i__3].r = z__[1].r, a[i__3].i = z__[1].i;
			i__3 = izero;
			a[i__3].r = z__[2].r, a[i__3].i = z__[2].i;
		    }
		}

/*              If IMAT > 7, set one column of the matrix to 0. */

		if (! zerot) {
		    izero = 0;
		} else if (imat == 8) {
		    izero = 1;
		    i__3 = n;
		    z__[1].r = a[i__3].r, z__[1].i = a[i__3].i;
		    i__3 = n;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		    if (n > 1) {
			z__[2].r = a[1].r, z__[2].i = a[1].i;
			a[1].r = 0.f, a[1].i = 0.f;
		    }
		} else if (imat == 9) {
		    izero = n;
		    i__3 = n * 3 - 2;
		    z__[0].r = a[i__3].r, z__[0].i = a[i__3].i;
		    i__3 = (n << 1) - 1;
		    z__[1].r = a[i__3].r, z__[1].i = a[i__3].i;
		    i__3 = n * 3 - 2;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		    i__3 = (n << 1) - 1;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		} else {
		    izero = (n + 1) / 2;
		    i__3 = n - 1;
		    for (i__ = izero; i__ <= i__3; ++i__) {
			i__4 = (n << 1) - 2 + i__;
			a[i__4].r = 0.f, a[i__4].i = 0.f;
			i__4 = n - 1 + i__;
			a[i__4].r = 0.f, a[i__4].i = 0.f;
			i__4 = i__;
			a[i__4].r = 0.f, a[i__4].i = 0.f;
/* L20: */
		    }
		    i__3 = n * 3 - 2;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		    i__3 = (n << 1) - 1;
		    a[i__3].r = 0.f, a[i__3].i = 0.f;
		}
	    }

/* +    TEST 1   
             Factor A as L*U and compute the ratio   
                norm(L*U - A) / (n * norm(A) * EPS ) */

	    i__3 = n + (m << 1);
	    ccopy_(&i__3, &a[1], &c__1, &af[1], &c__1);
	    s_copy(srnamc_1.srnamt, "CGTTRF", (ftnlen)6, (ftnlen)6);
	    cgttrf_(&n, &af[1], &af[m + 1], &af[n + m + 1], &af[n + (m << 1) 
		    + 1], &iwork[1], &info);

/*           Check error code from CGTTRF. */

	    if (info != izero) {
		alaerh_(path, "CGTTRF", &info, &izero, " ", &n, &n, &c__1, &
			c__1, &c_n1, &imat, &nfail, &nerrs, nout);
	    }
	    trfcon = info != 0;

	    cgtt01_(&n, &a[1], &a[m + 1], &a[n + m + 1], &af[1], &af[m + 1], &
		    af[n + m + 1], &af[n + (m << 1) + 1], &iwork[1], &work[1],
		     &lda, &rwork[1], result);

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

	    if (result[0] >= *thresh) {
		if (nfail == 0 && nerrs == 0) {
		    alahd_(nout, path);
		}
		io___29.ciunit = *nout;
		s_wsfe(&io___29);
		do_fio(&c__1, (char *)&n, (ftnlen)sizeof(integer));
		do_fio(&c__1, (char *)&imat, (ftnlen)sizeof(integer));
		do_fio(&c__1, (char *)&c__1, (ftnlen)sizeof(integer));
		do_fio(&c__1, (char *)&result[0], (ftnlen)sizeof(real));
		e_wsfe();
		++nfail;
	    }
	    ++nrun;

	    for (itran = 1; itran <= 2; ++itran) {
		*(unsigned char *)trans = *(unsigned char *)&transs[itran - 1]
			;
		if (itran == 1) {
		    *(unsigned char *)norm = 'O';
		} else {
		    *(unsigned char *)norm = 'I';
		}
		anorm = clangt_(norm, &n, &a[1], &a[m + 1], &a[n + m + 1]);

		if (! trfcon) {

/*                 Use CGTTRS to solve for one column at a time of   
                   inv(A), computing the maximum column sum as we go. */

		    ainvnm = 0.f;
		    i__3 = n;
		    for (i__ = 1; i__ <= i__3; ++i__) {
			i__4 = n;
			for (j = 1; j <= i__4; ++j) {
			    i__5 = j;
			    x[i__5].r = 0.f, x[i__5].i = 0.f;
/* L30: */
			}
			i__4 = i__;
			x[i__4].r = 1.f, x[i__4].i = 0.f;
			cgttrs_(trans, &n, &c__1, &af[1], &af[m + 1], &af[n + 
				m + 1], &af[n + (m << 1) + 1], &iwork[1], &x[
				1], &lda, &info);
/* Computing MAX */
			r__1 = ainvnm, r__2 = scasum_(&n, &x[1], &c__1);
			ainvnm = dmax(r__1,r__2);
/* L40: */
		    }

/*                 Compute RCONDC = 1 / (norm(A) * norm(inv(A)) */

		    if (anorm <= 0.f || ainvnm <= 0.f) {
			rcondc = 1.f;
		    } else {
			rcondc = 1.f / anorm / ainvnm;
		    }
		    if (itran == 1) {
			rcondo = rcondc;
		    } else {
			rcondi = rcondc;
		    }
		} else {
		    rcondc = 0.f;
		}

/* +    TEST 7   
                Estimate the reciprocal of the condition number of the   
                matrix. */

		s_copy(srnamc_1.srnamt, "CGTCON", (ftnlen)6, (ftnlen)6);
		cgtcon_(norm, &n, &af[1], &af[m + 1], &af[n + m + 1], &af[n + 
			(m << 1) + 1], &iwork[1], &anorm, &rcond, &work[1], &
			info);

/*              Check error code from CGTCON. */

		if (info != 0) {
		    alaerh_(path, "CGTCON", &info, &c__0, norm, &n, &n, &c_n1,
			     &c_n1, &c_n1, &imat, &nfail, &nerrs, nout);
		}

		result[6] = sget06_(&rcond, &rcondc);

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

		if (result[6] >= *thresh) {
		    if (nfail == 0 && nerrs == 0) {
			alahd_(nout, path);
		    }
		    io___39.ciunit = *nout;
		    s_wsfe(&io___39);
		    do_fio(&c__1, norm, (ftnlen)1);
		    do_fio(&c__1, (char *)&n, (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(real));
		    e_wsfe();
		    ++nfail;
		}
		++nrun;
/* L50: */
	    }

/*           Skip the remaining tests if the matrix is singular. */

	    if (trfcon) {
		goto L100;
	    }

	    i__3 = *nns;
	    for (irhs = 1; irhs <= i__3; ++irhs) {
		nrhs = nsval[irhs];

/*              Generate NRHS random solution vectors. */

		ix = 1;
		i__4 = nrhs;
		for (j = 1; j <= i__4; ++j) {
		    clarnv_(&c__2, iseed, &n, &xact[ix]);
		    ix += lda;
/* L60: */
		}

		for (itran = 1; itran <= 3; ++itran) {
		    *(unsigned char *)trans = *(unsigned char *)&transs[itran 
			    - 1];
		    if (itran == 1) {
			rcondc = rcondo;
		    } else {
			rcondc = rcondi;
		    }

/*                 Set the right hand side. */

		    clagtm_(trans, &n, &nrhs, &c_b63, &a[1], &a[m + 1], &a[n 
			    + m + 1], &xact[1], &lda, &c_b64, &b[1], &lda);

/* +    TEST 2   
                Solve op(A) * X = B and compute the residual. */

		    clacpy_("Full", &n, &nrhs, &b[1], &lda, &x[1], &lda);
		    s_copy(srnamc_1.srnamt, "CGTTRS", (ftnlen)6, (ftnlen)6);
		    cgttrs_(trans, &n, &nrhs, &af[1], &af[m + 1], &af[n + m + 
			    1], &af[n + (m << 1) + 1], &iwork[1], &x[1], &lda,
			     &info);

/*              Check error code from CGTTRS. */

		    if (info != 0) {
			alaerh_(path, "CGTTRS", &info, &c__0, trans, &n, &n, &
				c_n1, &c_n1, &nrhs, &imat, &nfail, &nerrs, 
				nout);
		    }

		    clacpy_("Full", &n, &nrhs, &b[1], &lda, &work[1], &lda);
		    cgtt02_(trans, &n, &nrhs, &a[1], &a[m + 1], &a[n + m + 1],
			     &x[1], &lda, &work[1], &lda, &rwork[1], &result[
			    1]);

/* +    TEST 3   
                Check solution from generated exact solution. */

		    cget04_(&n, &nrhs, &x[1], &lda, &xact[1], &lda, &rcondc, &
			    result[2]);

/* +    TESTS 4, 5, and 6   
                Use iterative refinement to improve the solution. */

		    s_copy(srnamc_1.srnamt, "CGTRFS", (ftnlen)6, (ftnlen)6);
		    cgtrfs_(trans, &n, &nrhs, &a[1], &a[m + 1], &a[n + m + 1],
			     &af[1], &af[m + 1], &af[n + m + 1], &af[n + (m <<
			     1) + 1], &iwork[1], &b[1], &lda, &x[1], &lda, &
			    rwork[1], &rwork[nrhs + 1], &work[1], &rwork[(
			    nrhs << 1) + 1], &info);

/*              Check error code from CGTRFS. */

		    if (info != 0) {
			alaerh_(path, "CGTRFS", &info, &c__0, trans, &n, &n, &
				c_n1, &c_n1, &nrhs, &imat, &nfail, &nerrs, 
				nout);
		    }

		    cget04_(&n, &nrhs, &x[1], &lda, &xact[1], &lda, &rcondc, &
			    result[3]);
		    cgtt05_(trans, &n, &nrhs, &a[1], &a[m + 1], &a[n + m + 1],
			     &b[1], &lda, &x[1], &lda, &xact[1], &lda, &rwork[
			    1], &rwork[nrhs + 1], &result[4]);

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

		    for (k = 2; k <= 6; ++k) {
			if (result[k - 1] >= *thresh) {
			    if (nfail == 0 && nerrs == 0) {
				alahd_(nout, path);
			    }
			    io___44.ciunit = *nout;
			    s_wsfe(&io___44);
			    do_fio(&c__1, trans, (ftnlen)1);
			    do_fio(&c__1, (char *)&n, (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(real));
			    e_wsfe();
			    ++nfail;
			}
/* L70: */
		    }
		    nrun += 5;
/* L80: */
		}
/* L90: */
	    }
L100:
	    ;
	}
/* L110: */
    }

/*     Print a summary of the results. */

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

    return 0;

/*     End of CCHKGT */

} /* cchkgt_ */
Exemplo n.º 3
0
/* Subroutine */ int cgtt02_(char *trans, integer *n, integer *nrhs, complex *
	dl, complex *d__, complex *du, complex *x, integer *ldx, complex *b, 
	integer *ldb, real *rwork, real *resid)
{
    /* System generated locals */
    integer b_dim1, b_offset, x_dim1, x_offset, i__1;
    real r__1, r__2;

    /* Local variables */
    integer j;
    real eps;
    extern logical lsame_(char *, char *);
    real anorm, bnorm, xnorm;
    extern doublereal slamch_(char *), clangt_(char *, integer *, 
	    complex *, complex *, complex *);
    extern /* Subroutine */ int clagtm_(char *, integer *, integer *, real *, 
	    complex *, complex *, complex *, complex *, integer *, real *, 
	    complex *, integer *);
    extern doublereal scasum_(integer *, complex *, integer *);


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

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

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

/*  CGTT02 computes the residual for the solution to a tridiagonal */
/*  system of equations: */
/*     RESID = norm(B - op(A)*X) / (norm(A) * norm(X) * EPS), */
/*  where EPS is the machine epsilon. */

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

/*  TRANS   (input) CHARACTER */
/*          Specifies the form of the residual. */
/*          = 'N':  B - A * X     (No transpose) */
/*          = 'T':  B - A**T * X  (Transpose) */
/*          = 'C':  B - A**H * X  (Conjugate transpose) */

/*  N       (input) INTEGTER */
/*          The order of the matrix A.  N >= 0. */

/*  NRHS    (input) INTEGER */
/*          The number of right hand sides, i.e., the number of columns */
/*          of the matrices B and X.  NRHS >= 0. */

/*  DL      (input) COMPLEX array, dimension (N-1) */
/*          The (n-1) sub-diagonal elements of A. */

/*  D       (input) COMPLEX array, dimension (N) */
/*          The diagonal elements of A. */

/*  DU      (input) COMPLEX array, dimension (N-1) */
/*          The (n-1) super-diagonal elements of A. */

/*  X       (input) COMPLEX array, dimension (LDX,NRHS) */
/*          The computed solution vectors X. */

/*  LDX     (input) INTEGER */
/*          The leading dimension of the array X.  LDX >= max(1,N). */

/*  B       (input/output) COMPLEX array, dimension (LDB,NRHS) */
/*          On entry, the right hand side vectors for the system of */
/*          linear equations. */
/*          On exit, B is overwritten with the difference B - op(A)*X. */

/*  LDB     (input) INTEGER */
/*          The leading dimension of the array B.  LDB >= max(1,N). */

/*  RWORK   (workspace) REAL array, dimension (N) */

/*  RESID   (output) REAL */
/*          norm(B - op(A)*X) / (norm(A) * norm(X) * EPS) */

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

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

/*     Quick exit if N = 0 or NRHS = 0 */

    /* Parameter adjustments */
    --dl;
    --d__;
    --du;
    x_dim1 = *ldx;
    x_offset = 1 + x_dim1;
    x -= x_offset;
    b_dim1 = *ldb;
    b_offset = 1 + b_dim1;
    b -= b_offset;
    --rwork;

    /* Function Body */
    *resid = 0.f;
    if (*n <= 0 || *nrhs == 0) {
	return 0;
    }

/*     Compute the maximum over the number of right hand sides of */
/*        norm(B - op(A)*X) / ( norm(A) * norm(X) * EPS ). */

    if (lsame_(trans, "N")) {
	anorm = clangt_("1", n, &dl[1], &d__[1], &du[1]);
    } else {
	anorm = clangt_("I", n, &dl[1], &d__[1], &du[1]);
    }

/*     Exit with RESID = 1/EPS if ANORM = 0. */

    eps = slamch_("Epsilon");
    if (anorm <= 0.f) {
	*resid = 1.f / eps;
	return 0;
    }

/*     Compute B - op(A)*X. */

    clagtm_(trans, n, nrhs, &c_b6, &dl[1], &d__[1], &du[1], &x[x_offset], ldx, 
	     &c_b7, &b[b_offset], ldb);

    i__1 = *nrhs;
    for (j = 1; j <= i__1; ++j) {
	bnorm = scasum_(n, &b[j * b_dim1 + 1], &c__1);
	xnorm = scasum_(n, &x[j * x_dim1 + 1], &c__1);
	if (xnorm <= 0.f) {
	    *resid = 1.f / eps;
	} else {
/* Computing MAX */
	    r__1 = *resid, r__2 = bnorm / anorm / xnorm / eps;
	    *resid = dmax(r__1,r__2);
	}
/* L10: */
    }

    return 0;

/*     End of CGTT02 */

} /* cgtt02_ */
Exemplo n.º 4
0
/* Subroutine */ int cgtsvx_(char *fact, char *trans, integer *n, integer *
	nrhs, complex *dl, complex *d__, complex *du, complex *dlf, complex *
	df, complex *duf, complex *du2, integer *ipiv, complex *b, integer *
	ldb, complex *x, integer *ldx, real *rcond, real *ferr, real *berr, 
	complex *work, real *rwork, integer *info)
{
/*  -- LAPACK routine (version 3.0) --   
       Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   
       Courant Institute, Argonne National Lab, and Rice University   
       June 30, 1999   


    Purpose   
    =======   

    CGTSVX uses the LU factorization to compute the solution to a complex   
    system of linear equations A * X = B, A**T * X = B, or A**H * X = B,   
    where A is a tridiagonal matrix of order N and X and B are N-by-NRHS   
    matrices.   

    Error bounds on the solution and a condition estimate are also   
    provided.   

    Description   
    ===========   

    The following steps are performed:   

    1. If FACT = 'N', the LU decomposition is used to factor the matrix A   
       as A = L * U, where L is a product of permutation and unit lower   
       bidiagonal matrices and U is upper triangular with nonzeros in   
       only the main diagonal and first two superdiagonals.   

    2. If some U(i,i)=0, so that U is exactly singular, then the routine   
       returns with INFO = i. Otherwise, the factored form of A is used   
       to estimate the condition number of the matrix A.  If the   
       reciprocal of the condition number is less than machine precision,   
       INFO = N+1 is returned as a warning, but the routine still goes on   
       to solve for X and compute error bounds as described below.   

    3. The system of equations is solved for X using the factored form   
       of A.   

    4. Iterative refinement is applied to improve the computed solution   
       matrix and calculate error bounds and backward error estimates   
       for it.   

    Arguments   
    =========   

    FACT    (input) CHARACTER*1   
            Specifies whether or not the factored form of A has been   
            supplied on entry.   
            = 'F':  DLF, DF, DUF, DU2, and IPIV contain the factored form   
                    of A; DL, D, DU, DLF, DF, DUF, DU2 and IPIV will not   
                    be modified.   
            = 'N':  The matrix will be copied to DLF, DF, and DUF   
                    and factored.   

    TRANS   (input) CHARACTER*1   
            Specifies the form of the system of equations:   
            = 'N':  A * X = B     (No transpose)   
            = 'T':  A**T * X = B  (Transpose)   
            = 'C':  A**H * X = B  (Conjugate transpose)   

    N       (input) INTEGER   
            The order of the matrix A.  N >= 0.   

    NRHS    (input) INTEGER   
            The number of right hand sides, i.e., the number of columns   
            of the matrix B.  NRHS >= 0.   

    DL      (input) COMPLEX array, dimension (N-1)   
            The (n-1) subdiagonal elements of A.   

    D       (input) COMPLEX array, dimension (N)   
            The n diagonal elements of A.   

    DU      (input) COMPLEX array, dimension (N-1)   
            The (n-1) superdiagonal elements of A.   

    DLF     (input or output) COMPLEX array, dimension (N-1)   
            If FACT = 'F', then DLF is an input argument and on entry   
            contains the (n-1) multipliers that define the matrix L from   
            the LU factorization of A as computed by CGTTRF.   

            If FACT = 'N', then DLF is an output argument and on exit   
            contains the (n-1) multipliers that define the matrix L from   
            the LU factorization of A.   

    DF      (input or output) COMPLEX array, dimension (N)   
            If FACT = 'F', then DF is an input argument and on entry   
            contains the n diagonal elements of the upper triangular   
            matrix U from the LU factorization of A.   

            If FACT = 'N', then DF is an output argument and on exit   
            contains the n diagonal elements of the upper triangular   
            matrix U from the LU factorization of A.   

    DUF     (input or output) COMPLEX array, dimension (N-1)   
            If FACT = 'F', then DUF is an input argument and on entry   
            contains the (n-1) elements of the first superdiagonal of U.   

            If FACT = 'N', then DUF is an output argument and on exit   
            contains the (n-1) elements of the first superdiagonal of U.   

    DU2     (input or output) COMPLEX array, dimension (N-2)   
            If FACT = 'F', then DU2 is an input argument and on entry   
            contains the (n-2) elements of the second superdiagonal of   
            U.   

            If FACT = 'N', then DU2 is an output argument and on exit   
            contains the (n-2) elements of the second superdiagonal of   
            U.   

    IPIV    (input or output) INTEGER array, dimension (N)   
            If FACT = 'F', then IPIV is an input argument and on entry   
            contains the pivot indices from the LU factorization of A as   
            computed by CGTTRF.   

            If FACT = 'N', then IPIV is an output argument and on exit   
            contains the pivot indices from the LU factorization of A;   
            row i of the matrix was interchanged with row IPIV(i).   
            IPIV(i) will always be either i or i+1; IPIV(i) = i indicates   
            a row interchange was not required.   

    B       (input) COMPLEX array, dimension (LDB,NRHS)   
            The N-by-NRHS right hand side matrix B.   

    LDB     (input) INTEGER   
            The leading dimension of the array B.  LDB >= max(1,N).   

    X       (output) COMPLEX array, dimension (LDX,NRHS)   
            If INFO = 0 or INFO = N+1, the N-by-NRHS solution matrix X.   

    LDX     (input) INTEGER   
            The leading dimension of the array X.  LDX >= max(1,N).   

    RCOND   (output) REAL   
            The estimate of the reciprocal condition number of the matrix   
            A.  If RCOND is less than the machine precision (in   
            particular, if RCOND = 0), the matrix is singular to working   
            precision.  This condition is indicated by a return code of   
            INFO > 0.   

    FERR    (output) REAL array, dimension (NRHS)   
            The estimated forward error bound for each solution vector   
            X(j) (the j-th column of the solution matrix X).   
            If XTRUE is the true solution corresponding to X(j), FERR(j)   
            is an estimated upper bound for the magnitude of the largest   
            element in (X(j) - XTRUE) divided by the magnitude of the   
            largest element in X(j).  The estimate is as reliable as   
            the estimate for RCOND, and is almost always a slight   
            overestimate of the true error.   

    BERR    (output) REAL array, dimension (NRHS)   
            The componentwise relative backward error of each solution   
            vector X(j) (i.e., the smallest relative change in   
            any element of A or B that makes X(j) an exact solution).   

    WORK    (workspace) COMPLEX array, dimension (2*N)   

    RWORK   (workspace) REAL array, dimension (N)   

    INFO    (output) INTEGER   
            = 0:  successful exit   
            < 0:  if INFO = -i, the i-th argument had an illegal value   
            > 0:  if INFO = i, and i is   
                  <= N:  U(i,i) is exactly zero.  The factorization   
                         has not been completed unless i = N, but the   
                         factor U is exactly singular, so the solution   
                         and error bounds could not be computed.   
                         RCOND = 0 is returned.   
                  = N+1: U is nonsingular, but RCOND is less than machine   
                         precision, meaning that the matrix is singular   
                         to working precision.  Nevertheless, the   
                         solution and error bounds are computed because   
                         there are a number of situations where the   
                         computed solution can be more accurate than the   
                         value of RCOND would suggest.   

    =====================================================================   


       Parameter adjustments */
    /* Table of constant values */
    static integer c__1 = 1;
    
    /* System generated locals */
    integer b_dim1, b_offset, x_dim1, x_offset, i__1;
    /* Local variables */
    static char norm[1];
    extern logical lsame_(char *, char *);
    static real anorm;
    extern /* Subroutine */ int ccopy_(integer *, complex *, integer *, 
	    complex *, integer *);
    extern doublereal slamch_(char *), clangt_(char *, integer *, 
	    complex *, complex *, complex *);
    static logical nofact;
    extern /* Subroutine */ int clacpy_(char *, integer *, integer *, complex 
	    *, integer *, complex *, integer *), cgtcon_(char *, 
	    integer *, complex *, complex *, complex *, complex *, integer *, 
	    real *, real *, complex *, integer *), xerbla_(char *, 
	    integer *), cgtrfs_(char *, integer *, integer *, complex 
	    *, complex *, complex *, complex *, complex *, complex *, complex 
	    *, integer *, complex *, integer *, complex *, integer *, real *, 
	    real *, complex *, real *, integer *), cgttrf_(integer *, 
	    complex *, complex *, complex *, complex *, integer *, integer *);
    static logical notran;
    extern /* Subroutine */ int cgttrs_(char *, integer *, integer *, complex 
	    *, complex *, complex *, complex *, integer *, complex *, integer 
	    *, integer *);


    --dl;
    --d__;
    --du;
    --dlf;
    --df;
    --duf;
    --du2;
    --ipiv;
    b_dim1 = *ldb;
    b_offset = 1 + b_dim1 * 1;
    b -= b_offset;
    x_dim1 = *ldx;
    x_offset = 1 + x_dim1 * 1;
    x -= x_offset;
    --ferr;
    --berr;
    --work;
    --rwork;

    /* Function Body */
    *info = 0;
    nofact = lsame_(fact, "N");
    notran = lsame_(trans, "N");
    if (! nofact && ! lsame_(fact, "F")) {
	*info = -1;
    } else if (! notran && ! lsame_(trans, "T") && ! 
	    lsame_(trans, "C")) {
	*info = -2;
    } else if (*n < 0) {
	*info = -3;
    } else if (*nrhs < 0) {
	*info = -4;
    } else if (*ldb < max(1,*n)) {
	*info = -14;
    } else if (*ldx < max(1,*n)) {
	*info = -16;
    }
    if (*info != 0) {
	i__1 = -(*info);
	xerbla_("CGTSVX", &i__1);
	return 0;
    }

    if (nofact) {

/*        Compute the LU factorization of A. */

	ccopy_(n, &d__[1], &c__1, &df[1], &c__1);
	if (*n > 1) {
	    i__1 = *n - 1;
	    ccopy_(&i__1, &dl[1], &c__1, &dlf[1], &c__1);
	    i__1 = *n - 1;
	    ccopy_(&i__1, &du[1], &c__1, &duf[1], &c__1);
	}
	cgttrf_(n, &dlf[1], &df[1], &duf[1], &du2[1], &ipiv[1], info);

/*        Return if INFO is non-zero. */

	if (*info != 0) {
	    if (*info > 0) {
		*rcond = 0.f;
	    }
	    return 0;
	}
    }

/*     Compute the norm of the matrix A. */

    if (notran) {
	*(unsigned char *)norm = '1';
    } else {
	*(unsigned char *)norm = 'I';
    }
    anorm = clangt_(norm, n, &dl[1], &d__[1], &du[1]);

/*     Compute the reciprocal of the condition number of A. */

    cgtcon_(norm, n, &dlf[1], &df[1], &duf[1], &du2[1], &ipiv[1], &anorm, 
	    rcond, &work[1], info);

/*     Set INFO = N+1 if the matrix is singular to working precision. */

    if (*rcond < slamch_("Epsilon")) {
	*info = *n + 1;
    }

/*     Compute the solution vectors X. */

    clacpy_("Full", n, nrhs, &b[b_offset], ldb, &x[x_offset], ldx);
    cgttrs_(trans, n, nrhs, &dlf[1], &df[1], &duf[1], &du2[1], &ipiv[1], &x[
	    x_offset], ldx, info);

/*     Use iterative refinement to improve the computed solutions and   
       compute error bounds and backward error estimates for them. */

    cgtrfs_(trans, n, nrhs, &dl[1], &d__[1], &du[1], &dlf[1], &df[1], &duf[1],
	     &du2[1], &ipiv[1], &b[b_offset], ldb, &x[x_offset], ldx, &ferr[1]
	    , &berr[1], &work[1], &rwork[1], info);

    return 0;

/*     End of CGTSVX */

} /* cgtsvx_ */