Exemplo n.º 1
0
/* Subroutine */ int dpbsvx_(char *fact, char *uplo, integer *n, integer *kd, 
	integer *nrhs, doublereal *ab, integer *ldab, doublereal *afb, 
	integer *ldafb, char *equed, doublereal *s, doublereal *b, integer *
	ldb, doublereal *x, integer *ldx, doublereal *rcond, doublereal *ferr, 
	 doublereal *berr, doublereal *work, integer *iwork, integer *info)
{
    /* System generated locals */
    integer ab_dim1, ab_offset, afb_dim1, afb_offset, b_dim1, b_offset, 
	    x_dim1, x_offset, i__1, i__2;
    doublereal d__1, d__2;

    /* Local variables */
    integer i__, j, j1, j2;
    doublereal amax, smin, smax;
    extern logical lsame_(char *, char *);
    doublereal scond, anorm;
    extern /* Subroutine */ int dcopy_(integer *, doublereal *, integer *, 
	    doublereal *, integer *);
    logical equil, rcequ, upper;
    extern doublereal dlamch_(char *), dlansb_(char *, char *, 
	    integer *, integer *, doublereal *, integer *, doublereal *);
    extern /* Subroutine */ int dpbcon_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, doublereal *, doublereal *, 
	     integer *, integer *), dlaqsb_(char *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, char *);
    logical nofact;
    extern /* Subroutine */ int dlacpy_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, integer *), 
	    xerbla_(char *, integer *), dpbequ_(char *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, integer *);
    doublereal bignum;
    extern /* Subroutine */ int dpbrfs_(char *, integer *, integer *, integer 
	    *, doublereal *, integer *, doublereal *, integer *, doublereal *, 
	     integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, integer *, integer *), dpbtrf_(char *, 
	    integer *, integer *, doublereal *, integer *, integer *);
    integer infequ;
    extern /* Subroutine */ int dpbtrs_(char *, integer *, integer *, integer 
	    *, doublereal *, integer *, doublereal *, integer *, integer *);
    doublereal smlnum;


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

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

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

/*  DPBSVX uses the Cholesky factorization A = U**T*U or A = L*L**T to */
/*  compute the solution to a real system of linear equations */
/*     A * X = B, */
/*  where A is an N-by-N symmetric positive definite band matrix 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 = 'E', real scaling factors are computed to equilibrate */
/*     the system: */
/*        diag(S) * A * diag(S) * inv(diag(S)) * X = diag(S) * B */
/*     Whether or not the system will be equilibrated depends on the */
/*     scaling of the matrix A, but if equilibration is used, A is */
/*     overwritten by diag(S)*A*diag(S) and B by diag(S)*B. */

/*  2. If FACT = 'N' or 'E', the Cholesky decomposition is used to */
/*     factor the matrix A (after equilibration if FACT = 'E') as */
/*        A = U**T * U,  if UPLO = 'U', or */
/*        A = L * L**T,  if UPLO = 'L', */
/*     where U is an upper triangular band matrix, and L is a lower */
/*     triangular band matrix. */

/*  3. If the leading i-by-i principal minor is not positive definite, */
/*     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. */

/*  4. The system of equations is solved for X using the factored form */
/*     of A. */

/*  5. Iterative refinement is applied to improve the computed solution */
/*     matrix and calculate error bounds and backward error estimates */
/*     for it. */

/*  6. If equilibration was used, the matrix X is premultiplied by */
/*     diag(S) so that it solves the original system before */
/*     equilibration. */

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

/*  FACT    (input) CHARACTER*1 */
/*          Specifies whether or not the factored form of the matrix A is */
/*          supplied on entry, and if not, whether the matrix A should be */
/*          equilibrated before it is factored. */
/*          = 'F':  On entry, AFB contains the factored form of A. */
/*                  If EQUED = 'Y', the matrix A has been equilibrated */
/*                  with scaling factors given by S.  AB and AFB will not */
/*                  be modified. */
/*          = 'N':  The matrix A will be copied to AFB and factored. */
/*          = 'E':  The matrix A will be equilibrated if necessary, then */
/*                  copied to AFB and factored. */

/*  UPLO    (input) CHARACTER*1 */
/*          = 'U':  Upper triangle of A is stored; */
/*          = 'L':  Lower triangle of A is stored. */

/*  N       (input) INTEGER */
/*          The number of linear equations, i.e., the order of the */
/*          matrix A.  N >= 0. */

/*  KD      (input) INTEGER */
/*          The number of superdiagonals of the matrix A if UPLO = 'U', */
/*          or the number of subdiagonals if UPLO = 'L'.  KD >= 0. */

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

/*  AB      (input/output) DOUBLE PRECISION array, dimension (LDAB,N) */
/*          On entry, the upper or lower triangle of the symmetric band */
/*          matrix A, stored in the first KD+1 rows of the array, except */
/*          if FACT = 'F' and EQUED = 'Y', then A must contain the */
/*          equilibrated matrix diag(S)*A*diag(S).  The j-th column of A */
/*          is stored in the j-th column of the array AB as follows: */
/*          if UPLO = 'U', AB(KD+1+i-j,j) = A(i,j) for max(1,j-KD)<=i<=j; */
/*          if UPLO = 'L', AB(1+i-j,j)    = A(i,j) for j<=i<=min(N,j+KD). */
/*          See below for further details. */

/*          On exit, if FACT = 'E' and EQUED = 'Y', A is overwritten by */
/*          diag(S)*A*diag(S). */

/*  LDAB    (input) INTEGER */
/*          The leading dimension of the array A.  LDAB >= KD+1. */

/*  AFB     (input or output) DOUBLE PRECISION array, dimension (LDAFB,N) */
/*          If FACT = 'F', then AFB is an input argument and on entry */
/*          contains the triangular factor U or L from the Cholesky */
/*          factorization A = U**T*U or A = L*L**T of the band matrix */
/*          A, in the same storage format as A (see AB).  If EQUED = 'Y', */
/*          then AFB is the factored form of the equilibrated matrix A. */

/*          If FACT = 'N', then AFB is an output argument and on exit */
/*          returns the triangular factor U or L from the Cholesky */
/*          factorization A = U**T*U or A = L*L**T. */

/*          If FACT = 'E', then AFB is an output argument and on exit */
/*          returns the triangular factor U or L from the Cholesky */
/*          factorization A = U**T*U or A = L*L**T of the equilibrated */
/*          matrix A (see the description of A for the form of the */
/*          equilibrated matrix). */

/*  LDAFB   (input) INTEGER */
/*          The leading dimension of the array AFB.  LDAFB >= KD+1. */

/*  EQUED   (input or output) CHARACTER*1 */
/*          Specifies the form of equilibration that was done. */
/*          = 'N':  No equilibration (always true if FACT = 'N'). */
/*          = 'Y':  Equilibration was done, i.e., A has been replaced by */
/*                  diag(S) * A * diag(S). */
/*          EQUED is an input argument if FACT = 'F'; otherwise, it is an */
/*          output argument. */

/*  S       (input or output) DOUBLE PRECISION array, dimension (N) */
/*          The scale factors for A; not accessed if EQUED = 'N'.  S is */
/*          an input argument if FACT = 'F'; otherwise, S is an output */
/*          argument.  If FACT = 'F' and EQUED = 'Y', each element of S */
/*          must be positive. */

/*  B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS) */
/*          On entry, the N-by-NRHS right hand side matrix B. */
/*          On exit, if EQUED = 'N', B is not modified; if EQUED = 'Y', */
/*          B is overwritten by diag(S) * B. */

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

/*  X       (output) DOUBLE PRECISION array, dimension (LDX,NRHS) */
/*          If INFO = 0 or INFO = N+1, the N-by-NRHS solution matrix X to */
/*          the original system of equations.  Note that if EQUED = 'Y', */
/*          A and B are modified on exit, and the solution to the */
/*          equilibrated system is inv(diag(S))*X. */

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

/*  RCOND   (output) DOUBLE PRECISION */
/*          The estimate of the reciprocal condition number of the matrix */
/*          A after equilibration (if done).  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) DOUBLE PRECISION 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) DOUBLE PRECISION 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) DOUBLE PRECISION array, dimension (3*N) */

/*  IWORK   (workspace) INTEGER 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:  the leading minor of order i of A is */
/*                       not positive definite, so the factorization */
/*                       could not be completed, and the solution has not */
/*                       been 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. */

/*  Further Details */
/*  =============== */

/*  The band storage scheme is illustrated by the following example, when */
/*  N = 6, KD = 2, and UPLO = 'U': */

/*  Two-dimensional storage of the symmetric matrix A: */

/*     a11  a12  a13 */
/*          a22  a23  a24 */
/*               a33  a34  a35 */
/*                    a44  a45  a46 */
/*                         a55  a56 */
/*     (aij=conjg(aji))         a66 */

/*  Band storage of the upper triangle of A: */

/*      *    *   a13  a24  a35  a46 */
/*      *   a12  a23  a34  a45  a56 */
/*     a11  a22  a33  a44  a55  a66 */

/*  Similarly, if UPLO = 'L' the format of A is as follows: */

/*     a11  a22  a33  a44  a55  a66 */
/*     a21  a32  a43  a54  a65   * */
/*     a31  a42  a53  a64   *    * */

/*  Array elements marked * are not used by the routine. */

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

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

    /* Parameter adjustments */
    ab_dim1 = *ldab;
    ab_offset = 1 + ab_dim1;
    ab -= ab_offset;
    afb_dim1 = *ldafb;
    afb_offset = 1 + afb_dim1;
    afb -= afb_offset;
    --s;
    b_dim1 = *ldb;
    b_offset = 1 + b_dim1;
    b -= b_offset;
    x_dim1 = *ldx;
    x_offset = 1 + x_dim1;
    x -= x_offset;
    --ferr;
    --berr;
    --work;
    --iwork;

    /* Function Body */
    *info = 0;
    nofact = lsame_(fact, "N");
    equil = lsame_(fact, "E");
    upper = lsame_(uplo, "U");
    if (nofact || equil) {
	*(unsigned char *)equed = 'N';
	rcequ = FALSE_;
    } else {
	rcequ = lsame_(equed, "Y");
	smlnum = dlamch_("Safe minimum");
	bignum = 1. / smlnum;
    }

/*     Test the input parameters. */

    if (! nofact && ! equil && ! lsame_(fact, "F")) {
	*info = -1;
    } else if (! upper && ! lsame_(uplo, "L")) {
	*info = -2;
    } else if (*n < 0) {
	*info = -3;
    } else if (*kd < 0) {
	*info = -4;
    } else if (*nrhs < 0) {
	*info = -5;
    } else if (*ldab < *kd + 1) {
	*info = -7;
    } else if (*ldafb < *kd + 1) {
	*info = -9;
    } else if (lsame_(fact, "F") && ! (rcequ || lsame_(
	    equed, "N"))) {
	*info = -10;
    } else {
	if (rcequ) {
	    smin = bignum;
	    smax = 0.;
	    i__1 = *n;
	    for (j = 1; j <= i__1; ++j) {
/* Computing MIN */
		d__1 = smin, d__2 = s[j];
		smin = min(d__1,d__2);
/* Computing MAX */
		d__1 = smax, d__2 = s[j];
		smax = max(d__1,d__2);
/* L10: */
	    }
	    if (smin <= 0.) {
		*info = -11;
	    } else if (*n > 0) {
		scond = max(smin,smlnum) / min(smax,bignum);
	    } else {
		scond = 1.;
	    }
	}
	if (*info == 0) {
	    if (*ldb < max(1,*n)) {
		*info = -13;
	    } else if (*ldx < max(1,*n)) {
		*info = -15;
	    }
	}
    }

    if (*info != 0) {
	i__1 = -(*info);
	xerbla_("DPBSVX", &i__1);
	return 0;
    }

    if (equil) {

/*        Compute row and column scalings to equilibrate the matrix A. */

	dpbequ_(uplo, n, kd, &ab[ab_offset], ldab, &s[1], &scond, &amax, &
		infequ);
	if (infequ == 0) {

/*           Equilibrate the matrix. */

	    dlaqsb_(uplo, n, kd, &ab[ab_offset], ldab, &s[1], &scond, &amax, 
		    equed);
	    rcequ = lsame_(equed, "Y");
	}
    }

/*     Scale the right-hand side. */

    if (rcequ) {
	i__1 = *nrhs;
	for (j = 1; j <= i__1; ++j) {
	    i__2 = *n;
	    for (i__ = 1; i__ <= i__2; ++i__) {
		b[i__ + j * b_dim1] = s[i__] * b[i__ + j * b_dim1];
/* L20: */
	    }
/* L30: */
	}
    }

    if (nofact || equil) {

/*        Compute the Cholesky factorization A = U'*U or A = L*L'. */

	if (upper) {
	    i__1 = *n;
	    for (j = 1; j <= i__1; ++j) {
/* Computing MAX */
		i__2 = j - *kd;
		j1 = max(i__2,1);
		i__2 = j - j1 + 1;
		dcopy_(&i__2, &ab[*kd + 1 - j + j1 + j * ab_dim1], &c__1, &
			afb[*kd + 1 - j + j1 + j * afb_dim1], &c__1);
/* L40: */
	    }
	} else {
	    i__1 = *n;
	    for (j = 1; j <= i__1; ++j) {
/* Computing MIN */
		i__2 = j + *kd;
		j2 = min(i__2,*n);
		i__2 = j2 - j + 1;
		dcopy_(&i__2, &ab[j * ab_dim1 + 1], &c__1, &afb[j * afb_dim1 
			+ 1], &c__1);
/* L50: */
	    }
	}

	dpbtrf_(uplo, n, kd, &afb[afb_offset], ldafb, info);

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

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

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

    anorm = dlansb_("1", uplo, n, kd, &ab[ab_offset], ldab, &work[1]);

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

    dpbcon_(uplo, n, kd, &afb[afb_offset], ldafb, &anorm, rcond, &work[1], &
	    iwork[1], info);

/*     Compute the solution matrix X. */

    dlacpy_("Full", n, nrhs, &b[b_offset], ldb, &x[x_offset], ldx);
    dpbtrs_(uplo, n, kd, nrhs, &afb[afb_offset], ldafb, &x[x_offset], ldx, 
	    info);

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

    dpbrfs_(uplo, n, kd, nrhs, &ab[ab_offset], ldab, &afb[afb_offset], ldafb, 
	    &b[b_offset], ldb, &x[x_offset], ldx, &ferr[1], &berr[1], &work[1]
, &iwork[1], info);

/*     Transform the solution matrix X to a solution of the original */
/*     system. */

    if (rcequ) {
	i__1 = *nrhs;
	for (j = 1; j <= i__1; ++j) {
	    i__2 = *n;
	    for (i__ = 1; i__ <= i__2; ++i__) {
		x[i__ + j * x_dim1] = s[i__] * x[i__ + j * x_dim1];
/* L60: */
	    }
/* L70: */
	}
	i__1 = *nrhs;
	for (j = 1; j <= i__1; ++j) {
	    ferr[j] /= scond;
/* L80: */
	}
    }

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

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

    return 0;

/*     End of DPBSVX */

} /* dpbsvx_ */
Exemplo n.º 2
0
/* Subroutine */ int dpbsvx_(char *fact, char *uplo, integer *n, integer *kd, 
	integer *nrhs, doublereal *ab, integer *ldab, doublereal *afb, 
	integer *ldafb, char *equed, doublereal *s, doublereal *b, integer *
	ldb, doublereal *x, integer *ldx, doublereal *rcond, doublereal *ferr,
	 doublereal *berr, doublereal *work, integer *iwork, integer *info)
{
/*  -- LAPACK driver routine (version 2.0) --   
       Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   
       Courant Institute, Argonne National Lab, and Rice University   
       September 30, 1994   


    Purpose   
    =======   

    DPBSVX uses the Cholesky factorization A = U**T*U or A = L*L**T to   
    compute the solution to a real system of linear equations   
       A * X = B,   
    where A is an N-by-N symmetric positive definite band matrix 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 = 'E', real scaling factors are computed to equilibrate   
       the system:   
          diag(S) * A * diag(S) * inv(diag(S)) * X = diag(S) * B   
       Whether or not the system will be equilibrated depends on the   
       scaling of the matrix A, but if equilibration is used, A is   
       overwritten by diag(S)*A*diag(S) and B by diag(S)*B.   

    2. If FACT = 'N' or 'E', the Cholesky decomposition is used to   
       factor the matrix A (after equilibration if FACT = 'E') as   
          A = U**T * U,  if UPLO = 'U', or   
          A = L * L**T,  if UPLO = 'L',   
       where U is an upper triangular band matrix, and L is a lower   
       triangular band matrix.   

    3. 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, steps 4-6 are skipped.   

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

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

    6. If equilibration was used, the matrix X is premultiplied by   
       diag(S) so that it solves the original system before   
       equilibration.   

    Arguments   
    =========   

    FACT    (input) CHARACTER*1   
            Specifies whether or not the factored form of the matrix A is 
  
            supplied on entry, and if not, whether the matrix A should be 
  
            equilibrated before it is factored.   
            = 'F':  On entry, AFB contains the factored form of A.   
                    If EQUED = 'Y', the matrix A has been equilibrated   
                    with scaling factors given by S.  AB and AFB will not 
  
                    be modified.   
            = 'N':  The matrix A will be copied to AFB and factored.   
            = 'E':  The matrix A will be equilibrated if necessary, then 
  
                    copied to AFB and factored.   

    UPLO    (input) CHARACTER*1   
            = 'U':  Upper triangle of A is stored;   
            = 'L':  Lower triangle of A is stored.   

    N       (input) INTEGER   
            The number of linear equations, i.e., the order of the   
            matrix A.  N >= 0.   

    KD      (input) INTEGER   
            The number of superdiagonals of the matrix A if UPLO = 'U',   
            or the number of subdiagonals if UPLO = 'L'.  KD >= 0.   

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

    AB      (input/output) DOUBLE PRECISION array, dimension (LDAB,N)   
            On entry, the upper or lower triangle of the symmetric band   
            matrix A, stored in the first KD+1 rows of the array, except 
  
            if FACT = 'F' and EQUED = 'Y', then A must contain the   
            equilibrated matrix diag(S)*A*diag(S).  The j-th column of A 
  
            is stored in the j-th column of the array AB as follows:   
            if UPLO = 'U', AB(KD+1+i-j,j) = A(i,j) for max(1,j-KD)<=i<=j; 
  
            if UPLO = 'L', AB(1+i-j,j)    = A(i,j) for j<=i<=min(N,j+KD). 
  
            See below for further details.   

            On exit, if FACT = 'E' and EQUED = 'Y', A is overwritten by   
            diag(S)*A*diag(S).   

    LDAB    (input) INTEGER   
            The leading dimension of the array A.  LDAB >= KD+1.   

    AFB     (input or output) DOUBLE PRECISION array, dimension (LDAFB,N) 
  
            If FACT = 'F', then AFB is an input argument and on entry   
            contains the triangular factor U or L from the Cholesky   
            factorization A = U**T*U or A = L*L**T of the band matrix   
            A, in the same storage format as A (see AB).  If EQUED = 'Y', 
  
            then AFB is the factored form of the equilibrated matrix A.   

            If FACT = 'N', then AFB is an output argument and on exit   
            returns the triangular factor U or L from the Cholesky   
            factorization A = U**T*U or A = L*L**T.   

            If FACT = 'E', then AFB is an output argument and on exit   
            returns the triangular factor U or L from the Cholesky   
            factorization A = U**T*U or A = L*L**T of the equilibrated   
            matrix A (see the description of A for the form of the   
            equilibrated matrix).   

    LDAFB   (input) INTEGER   
            The leading dimension of the array AFB.  LDAFB >= KD+1.   

    EQUED   (input or output) CHARACTER*1   
            Specifies the form of equilibration that was done.   
            = 'N':  No equilibration (always true if FACT = 'N').   
            = 'Y':  Equilibration was done, i.e., A has been replaced by 
  
                    diag(S) * A * diag(S).   
            EQUED is an input argument if FACT = 'F'; otherwise, it is an 
  
            output argument.   

    S       (input or output) DOUBLE PRECISION array, dimension (N)   
            The scale factors for A; not accessed if EQUED = 'N'.  S is   
            an input argument if FACT = 'F'; otherwise, S is an output   
            argument.  If FACT = 'F' and EQUED = 'Y', each element of S   
            must be positive.   

    B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)   
            On entry, the N-by-NRHS right hand side matrix B.   
            On exit, if EQUED = 'N', B is not modified; if EQUED = 'Y',   
            B is overwritten by diag(S) * B.   

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

    X       (output) DOUBLE PRECISION array, dimension (LDX,NRHS)   
            If INFO = 0, the N-by-NRHS solution matrix X to the original 
  
            system of equations.  Note that if EQUED = 'Y', A and B are   
            modified on exit, and the solution to the equilibrated system 
  
            is inv(diag(S))*X.   

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

    RCOND   (output) DOUBLE PRECISION   
            The estimate of the reciprocal condition number of the matrix 
  
            A after equilibration (if done).  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, and the solution and 
  
            error bounds are not computed.   

    FERR    (output) DOUBLE PRECISION 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) DOUBLE PRECISION 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) DOUBLE PRECISION array, dimension (3*N)   

    IWORK   (workspace) INTEGER 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: the leading minor of order i of A is   
                       not positive definite, so the factorization could 
  
                       not be completed, and the solution has not been   
                       computed.   
                 = N+1: RCOND is less than machine precision.  The   
                       factorization has been completed, but the matrix   
                       is singular to working precision, and the solution 
  
                       and error bounds have not been computed.   

    Further Details   
    ===============   

    The band storage scheme is illustrated by the following example, when 
  
    N = 6, KD = 2, and UPLO = 'U':   

    Two-dimensional storage of the symmetric matrix A:   

       a11  a12  a13   
            a22  a23  a24   
                 a33  a34  a35   
                      a44  a45  a46   
                           a55  a56   
       (aij=conjg(aji))         a66   

    Band storage of the upper triangle of A:   

        *    *   a13  a24  a35  a46   
        *   a12  a23  a34  a45  a56   
       a11  a22  a33  a44  a55  a66   

    Similarly, if UPLO = 'L' the format of A is as follows:   

       a11  a22  a33  a44  a55  a66   
       a21  a32  a43  a54  a65   *   
       a31  a42  a53  a64   *    *   

    VISArray elements marked * are not used by the routine.   

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


    
   Parameter adjustments   
       Function Body */
    /* Table of constant values */
    static integer c__1 = 1;
    
    /* System generated locals */
    integer ab_dim1, ab_offset, afb_dim1, afb_offset, b_dim1, b_offset, 
	    x_dim1, x_offset, i__1, i__2;
    doublereal d__1, d__2;
    /* Local variables */
    static doublereal amax, smin, smax;
    static integer i, j;
    extern logical lsame_(char *, char *);
    static doublereal scond, anorm;
    extern /* Subroutine */ int dcopy_(integer *, doublereal *, integer *, 
	    doublereal *, integer *);
    static logical equil, rcequ, upper;
    static integer j1, j2;
    extern doublereal dlamch_(char *), dlansb_(char *, char *, 
	    integer *, integer *, doublereal *, integer *, doublereal *);
    extern /* Subroutine */ int dpbcon_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, doublereal *, doublereal *,
	     integer *, integer *), dlaqsb_(char *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, char *);
    static logical nofact;
    extern /* Subroutine */ int dlacpy_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, integer *), 
	    xerbla_(char *, integer *), dpbequ_(char *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, integer *);
    static doublereal bignum;
    extern /* Subroutine */ int dpbrfs_(char *, integer *, integer *, integer 
	    *, doublereal *, integer *, doublereal *, integer *, doublereal *,
	     integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, integer *, integer *), dpbtrf_(char *, 
	    integer *, integer *, doublereal *, integer *, integer *);
    static integer infequ;
    extern /* Subroutine */ int dpbtrs_(char *, integer *, integer *, integer 
	    *, doublereal *, integer *, doublereal *, integer *, integer *);
    static doublereal smlnum;



#define S(I) s[(I)-1]
#define FERR(I) ferr[(I)-1]
#define BERR(I) berr[(I)-1]
#define WORK(I) work[(I)-1]
#define IWORK(I) iwork[(I)-1]

#define AB(I,J) ab[(I)-1 + ((J)-1)* ( *ldab)]
#define AFB(I,J) afb[(I)-1 + ((J)-1)* ( *ldafb)]
#define B(I,J) b[(I)-1 + ((J)-1)* ( *ldb)]
#define X(I,J) x[(I)-1 + ((J)-1)* ( *ldx)]

    *info = 0;
    nofact = lsame_(fact, "N");
    equil = lsame_(fact, "E");
    upper = lsame_(uplo, "U");
    if (nofact || equil) {
	*(unsigned char *)equed = 'N';
	rcequ = FALSE_;
    } else {
	rcequ = lsame_(equed, "Y");
	smlnum = dlamch_("Safe minimum");
	bignum = 1. / smlnum;
    }

/*     Test the input parameters. */

    if (! nofact && ! equil && ! lsame_(fact, "F")) {
	*info = -1;
    } else if (! upper && ! lsame_(uplo, "L")) {
	*info = -2;
    } else if (*n < 0) {
	*info = -3;
    } else if (*kd < 0) {
	*info = -4;
    } else if (*nrhs < 0) {
	*info = -5;
    } else if (*ldab < *kd + 1) {
	*info = -7;
    } else if (*ldafb < *kd + 1) {
	*info = -9;
    } else if (lsame_(fact, "F") && ! (rcequ || lsame_(equed, "N"))) {
	*info = -10;
    } else {
	if (rcequ) {
	    smin = bignum;
	    smax = 0.;
	    i__1 = *n;
	    for (j = 1; j <= *n; ++j) {
/* Computing MIN */
		d__1 = smin, d__2 = S(j);
		smin = min(d__1,d__2);
/* Computing MAX */
		d__1 = smax, d__2 = S(j);
		smax = max(d__1,d__2);
/* L10: */
	    }
	    if (smin <= 0.) {
		*info = -11;
	    } else if (*n > 0) {
		scond = max(smin,smlnum) / min(smax,bignum);
	    } else {
		scond = 1.;
	    }
	}
	if (*info == 0) {
	    if (*ldb < max(1,*n)) {
		*info = -13;
	    } else if (*ldx < max(1,*n)) {
		*info = -15;
	    }
	}
    }

    if (*info != 0) {
	i__1 = -(*info);
	xerbla_("DPBSVX", &i__1);
	return 0;
    }

    if (equil) {

/*        Compute row and column scalings to equilibrate the matrix A.
 */

	dpbequ_(uplo, n, kd, &AB(1,1), ldab, &S(1), &scond, &amax, &
		infequ);
	if (infequ == 0) {

/*           Equilibrate the matrix. */

	    dlaqsb_(uplo, n, kd, &AB(1,1), ldab, &S(1), &scond, &amax, 
		    equed);
	    rcequ = lsame_(equed, "Y");
	}
    }

/*     Scale the right-hand side. */

    if (rcequ) {
	i__1 = *nrhs;
	for (j = 1; j <= *nrhs; ++j) {
	    i__2 = *n;
	    for (i = 1; i <= *n; ++i) {
		B(i,j) = S(i) * B(i,j);
/* L20: */
	    }
/* L30: */
	}
    }

    if (nofact || equil) {

/*        Compute the Cholesky factorization A = U'*U or A = L*L'. */

	if (upper) {
	    i__1 = *n;
	    for (j = 1; j <= *n; ++j) {
/* Computing MAX */
		i__2 = j - *kd;
		j1 = max(i__2,1);
		i__2 = j - j1 + 1;
		dcopy_(&i__2, &AB(*kd+1-j+j1,j), &c__1, &
			AFB(*kd+1-j+j1,j), &c__1);
/* L40: */
	    }
	} else {
	    i__1 = *n;
	    for (j = 1; j <= *n; ++j) {
/* Computing MIN */
		i__2 = j + *kd;
		j2 = min(i__2,*n);
		i__2 = j2 - j + 1;
		dcopy_(&i__2, &AB(1,j), &c__1, &AFB(1,j), &c__1);
/* L50: */
	    }
	}

	dpbtrf_(uplo, n, kd, &AFB(1,1), ldafb, info);

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

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

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

    anorm = dlansb_("1", uplo, n, kd, &AB(1,1), ldab, &WORK(1));

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

    dpbcon_(uplo, n, kd, &AFB(1,1), ldafb, &anorm, rcond, &WORK(1), &
	    IWORK(1), info);

/*     Return if the matrix is singular to working precision. */

    if (*rcond < dlamch_("Epsilon")) {
	*info = *n + 1;
	return 0;
    }

/*     Compute the solution matrix X. */

    dlacpy_("Full", n, nrhs, &B(1,1), ldb, &X(1,1), ldx);
    dpbtrs_(uplo, n, kd, nrhs, &AFB(1,1), ldafb, &X(1,1), ldx, 
	    info);

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

    dpbrfs_(uplo, n, kd, nrhs, &AB(1,1), ldab, &AFB(1,1), ldafb, 
	    &B(1,1), ldb, &X(1,1), ldx, &FERR(1), &BERR(1), &WORK(1)
	    , &IWORK(1), info);

/*     Transform the solution matrix X to a solution of the original   
       system. */

    if (rcequ) {
	i__1 = *nrhs;
	for (j = 1; j <= *nrhs; ++j) {
	    i__2 = *n;
	    for (i = 1; i <= *n; ++i) {
		X(i,j) = S(i) * X(i,j);
/* L60: */
	    }
/* L70: */
	}
	i__1 = *nrhs;
	for (j = 1; j <= *nrhs; ++j) {
	    FERR(j) /= scond;
/* L80: */
	}
    }

    return 0;

/*     End of DPBSVX */

} /* dpbsvx_ */
Exemplo n.º 3
0
/* Subroutine */ int dchkpb_(logical *dotype, integer *nn, integer *nval, 
	integer *nnb, integer *nbval, integer *nns, integer *nsval, 
	doublereal *thresh, logical *tsterr, integer *nmax, doublereal *a, 
	doublereal *afac, doublereal *ainv, doublereal *b, doublereal *x, 
	doublereal *xact, doublereal *work, doublereal *rwork, integer *iwork,
	 integer *nout)
{
    /* Initialized data */

    static integer iseedy[4] = { 1988,1989,1990,1991 };

    /* Format strings */
    static char fmt_9999[] = "(\002 UPLO='\002,a1,\002', N=\002,i5,\002, KD"
	    "=\002,i5,\002, NB=\002,i4,\002, type \002,i2,\002, test \002,i2"
	    ",\002, ratio= \002,g12.5)";
    static char fmt_9998[] = "(\002 UPLO='\002,a1,\002', N=\002,i5,\002, KD"
	    "=\002,i5,\002, NRHS=\002,i3,\002, type \002,i2,\002, test(\002,i"
	    "2,\002) = \002,g12.5)";
    static char fmt_9997[] = "(\002 UPLO='\002,a1,\002', N=\002,i5,\002, KD"
	    "=\002,i5,\002,\002,10x,\002 type \002,i2,\002, test(\002,i2,\002"
	    ") = \002,g12.5)";

    /* System generated locals */
    integer i__1, i__2, i__3, i__4, i__5, i__6;

    /* 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 integer ldab, ioff, mode, koff, imat, info;
    static char path[3], dist[1];
    static integer irhs, nrhs;
    static char uplo[1], type__[1];
    static integer nrun, i__;
    extern /* Subroutine */ int alahd_(integer *, char *);
    static integer k, n;
    extern /* Subroutine */ int dget04_(integer *, integer *, doublereal *, 
	    integer *, doublereal *, integer *, doublereal *, doublereal *);
    static integer nfail, iseed[4];
    extern doublereal dget06_(doublereal *, doublereal *);
    extern /* Subroutine */ int dpbt01_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, integer *, doublereal *, 
	    doublereal *), dpbt02_(char *, integer *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, integer *, 
	    doublereal *, integer *, doublereal *, doublereal *), 
	    dpbt05_(char *, integer *, integer *, integer *, doublereal *, 
	    integer *, doublereal *, integer *, doublereal *, integer *, 
	    doublereal *, integer *, doublereal *, doublereal *, doublereal *);
    static integer kdval[4];
    static doublereal rcond;
    static integer nimat;
    static doublereal anorm;
    extern /* Subroutine */ int dcopy_(integer *, doublereal *, integer *, 
	    doublereal *, integer *), dswap_(integer *, doublereal *, integer 
	    *, doublereal *, integer *);
    static integer iuplo, izero, i1, i2, nerrs;
    static logical zerot;
    static char xtype[1];
    extern /* Subroutine */ int dlatb4_(char *, integer *, integer *, integer 
	    *, char *, integer *, integer *, doublereal *, integer *, 
	    doublereal *, char *);
    static integer kd, nb, in, kl;
    extern doublereal dlange_(char *, integer *, integer *, doublereal *, 
	    integer *, doublereal *);
    extern /* Subroutine */ int alaerh_(char *, char *, integer *, integer *, 
	    char *, integer *, integer *, integer *, integer *, integer *, 
	    integer *, integer *, integer *, integer *);
    static integer iw, ku;
    extern doublereal dlansb_(char *, char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *);
    extern /* Subroutine */ int dpbcon_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, doublereal *, doublereal *,
	     integer *, integer *);
    static doublereal rcondc;
    static char packit[1];
    extern /* Subroutine */ int dlacpy_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, integer *), 
	    dlarhs_(char *, char *, char *, char *, integer *, integer *, 
	    integer *, integer *, integer *, doublereal *, integer *, 
	    doublereal *, integer *, doublereal *, integer *, integer *, 
	    integer *), dlaset_(char *, 
	    integer *, integer *, doublereal *, doublereal *, doublereal *, 
	    integer *), dpbrfs_(char *, integer *, integer *, integer 
	    *, doublereal *, integer *, doublereal *, integer *, doublereal *,
	     integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, integer *, integer *), dpbtrf_(char *, 
	    integer *, integer *, doublereal *, integer *, integer *),
	     alasum_(char *, integer *, integer *, integer *, integer *);
    static doublereal cndnum;
    extern /* Subroutine */ int dlatms_(integer *, integer *, char *, integer 
	    *, char *, doublereal *, integer *, doublereal *, doublereal *, 
	    integer *, integer *, char *, doublereal *, integer *, doublereal 
	    *, integer *);
    static doublereal ainvnm;
    extern /* Subroutine */ int derrpo_(char *, integer *), dpbtrs_(
	    char *, integer *, integer *, integer *, doublereal *, integer *, 
	    doublereal *, integer *, integer *), xlaenv_(integer *, 
	    integer *);
    static doublereal result[7];
    static integer lda, ikd, inb, nkd;

    /* Fortran I/O blocks */
    static cilist io___40 = { 0, 0, 0, fmt_9999, 0 };
    static cilist io___46 = { 0, 0, 0, fmt_9998, 0 };
    static cilist io___48 = { 0, 0, 0, fmt_9997, 0 };



/*  -- LAPACK test routine (version 3.0) --   
       Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd.,   
       Courant Institute, Argonne National Lab, and Rice University   
       December 7, 1999   


    Purpose   
    =======   

    DCHKPB tests DPBTRF, -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.   

    NNB     (input) INTEGER   
            The number of values of NB contained in the vector NBVAL.   

    NBVAL   (input) INTEGER array, dimension (NBVAL)   
            The values of the blocksize NB.   

    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 maximum value permitted for N, used in dimensioning the   
            work arrays.   

    A       (workspace) DOUBLE PRECISION array, dimension (NMAX*NMAX)   

    AFAC    (workspace) DOUBLE PRECISION array, dimension (NMAX*NMAX)   

    AINV    (workspace) DOUBLE PRECISION array, dimension (NMAX*NMAX)   

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

    X       (workspace) DOUBLE PRECISION array, dimension (NMAX*NSMAX)   

    XACT    (workspace) DOUBLE PRECISION array, dimension (NMAX*NSMAX)   

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

    RWORK   (workspace) DOUBLE PRECISION 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;
    --ainv;
    --afac;
    --a;
    --nsval;
    --nbval;
    --nval;
    --dotype;

    /* Function Body   

       Initialize constants and the random number seed. */

    s_copy(path, "Double precision", (ftnlen)1, (ftnlen)16);
    s_copy(path + 1, "PB", (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) {
	derrpo_(path, nout);
    }
    infoc_1.infot = 0;
    xlaenv_(&c__2, &c__2);
    kdval[0] = 0;

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

    i__1 = *nn;
    for (in = 1; in <= i__1; ++in) {
	n = nval[in];
	lda = max(n,1);
	*(unsigned char *)xtype = 'N';

/*        Set limits on the number of loop iterations.   

   Computing MAX */
	i__2 = 1, i__3 = min(n,4);
	nkd = max(i__2,i__3);
	nimat = 8;
	if (n == 0) {
	    nimat = 1;
	}

	kdval[1] = n + (n + 1) / 4;
	kdval[2] = (n * 3 - 1) / 4;
	kdval[3] = (n + 1) / 4;

	i__2 = nkd;
	for (ikd = 1; ikd <= i__2; ++ikd) {

/*           Do for KD = 0, (5*N+1)/4, (3N-1)/4, and (N+1)/4. This order   
             makes it easier to skip redundant values for small values   
             of N. */

	    kd = kdval[ikd - 1];
	    ldab = kd + 1;

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

	    for (iuplo = 1; iuplo <= 2; ++iuplo) {
		koff = 1;
		if (iuplo == 1) {
		    *(unsigned char *)uplo = 'U';
/* Computing MAX */
		    i__3 = 1, i__4 = kd + 2 - n;
		    koff = max(i__3,i__4);
		    *(unsigned char *)packit = 'Q';
		} else {
		    *(unsigned char *)uplo = 'L';
		    *(unsigned char *)packit = 'B';
		}

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

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

		    if (! dotype[imat]) {
			goto L60;
		    }

/*                 Skip types 2, 3, or 4 if the matrix size is too small. */

		    zerot = imat >= 2 && imat <= 4;
		    if (zerot && n < imat - 1) {
			goto L60;
		    }

		    if (! zerot || ! dotype[1]) {

/*                    Set up parameters with DLATB4 and generate a test   
                      matrix with DLATMS. */

			dlatb4_(path, &imat, &n, &n, type__, &kl, &ku, &anorm,
				 &mode, &cndnum, dist);

			s_copy(srnamc_1.srnamt, "DLATMS", (ftnlen)6, (ftnlen)
				6);
			dlatms_(&n, &n, dist, iseed, type__, &rwork[1], &mode,
				 &cndnum, &anorm, &kd, &kd, packit, &a[koff], 
				&ldab, &work[1], &info);

/*                    Check error code from DLATMS. */

			if (info != 0) {
			    alaerh_(path, "DLATMS", &info, &c__0, uplo, &n, &
				    n, &kd, &kd, &c_n1, &imat, &nfail, &nerrs,
				     nout);
			    goto L60;
			}
		    } else if (izero > 0) {

/*                    Use the same matrix for types 3 and 4 as for type   
                      2 by copying back the zeroed out column, */

			iw = (lda << 1) + 1;
			if (iuplo == 1) {
			    ioff = (izero - 1) * ldab + kd + 1;
			    i__4 = izero - i1;
			    dcopy_(&i__4, &work[iw], &c__1, &a[ioff - izero + 
				    i1], &c__1);
			    iw = iw + izero - i1;
			    i__4 = i2 - izero + 1;
/* Computing MAX */
			    i__6 = ldab - 1;
			    i__5 = max(i__6,1);
			    dcopy_(&i__4, &work[iw], &c__1, &a[ioff], &i__5);
			} else {
			    ioff = (i1 - 1) * ldab + 1;
			    i__4 = izero - i1;
/* Computing MAX */
			    i__6 = ldab - 1;
			    i__5 = max(i__6,1);
			    dcopy_(&i__4, &work[iw], &c__1, &a[ioff + izero - 
				    i1], &i__5);
			    ioff = (izero - 1) * ldab + 1;
			    iw = iw + izero - i1;
			    i__4 = i2 - izero + 1;
			    dcopy_(&i__4, &work[iw], &c__1, &a[ioff], &c__1);
			}
		    }

/*                 For types 2-4, zero one row and column of the matrix   
                   to test that INFO is returned correctly. */

		    izero = 0;
		    if (zerot) {
			if (imat == 2) {
			    izero = 1;
			} else if (imat == 3) {
			    izero = n;
			} else {
			    izero = n / 2 + 1;
			}

/*                    Save the zeroed out row and column in WORK(*,3) */

			iw = lda << 1;
/* Computing MIN */
			i__5 = (kd << 1) + 1;
			i__4 = min(i__5,n);
			for (i__ = 1; i__ <= i__4; ++i__) {
			    work[iw + i__] = 0.;
/* L20: */
			}
			++iw;
/* Computing MAX */
			i__4 = izero - kd;
			i1 = max(i__4,1);
/* Computing MIN */
			i__4 = izero + kd;
			i2 = min(i__4,n);

			if (iuplo == 1) {
			    ioff = (izero - 1) * ldab + kd + 1;
			    i__4 = izero - i1;
			    dswap_(&i__4, &a[ioff - izero + i1], &c__1, &work[
				    iw], &c__1);
			    iw = iw + izero - i1;
			    i__4 = i2 - izero + 1;
/* Computing MAX */
			    i__6 = ldab - 1;
			    i__5 = max(i__6,1);
			    dswap_(&i__4, &a[ioff], &i__5, &work[iw], &c__1);
			} else {
			    ioff = (i1 - 1) * ldab + 1;
			    i__4 = izero - i1;
/* Computing MAX */
			    i__6 = ldab - 1;
			    i__5 = max(i__6,1);
			    dswap_(&i__4, &a[ioff + izero - i1], &i__5, &work[
				    iw], &c__1);
			    ioff = (izero - 1) * ldab + 1;
			    iw = iw + izero - i1;
			    i__4 = i2 - izero + 1;
			    dswap_(&i__4, &a[ioff], &c__1, &work[iw], &c__1);
			}
		    }

/*                 Do for each value of NB in NBVAL */

		    i__4 = *nnb;
		    for (inb = 1; inb <= i__4; ++inb) {
			nb = nbval[inb];
			xlaenv_(&c__1, &nb);

/*                    Compute the L*L' or U'*U factorization of the band   
                      matrix. */

			i__5 = kd + 1;
			dlacpy_("Full", &i__5, &n, &a[1], &ldab, &afac[1], &
				ldab);
			s_copy(srnamc_1.srnamt, "DPBTRF", (ftnlen)6, (ftnlen)
				6);
			dpbtrf_(uplo, &n, &kd, &afac[1], &ldab, &info);

/*                    Check error code from DPBTRF. */

			if (info != izero) {
			    alaerh_(path, "DPBTRF", &info, &izero, uplo, &n, &
				    n, &kd, &kd, &nb, &imat, &nfail, &nerrs, 
				    nout);
			    goto L50;
			}

/*                    Skip the tests if INFO is not 0. */

			if (info != 0) {
			    goto L50;
			}

/* +    TEST 1   
                      Reconstruct matrix from factors and compute   
                      residual. */

			i__5 = kd + 1;
			dlacpy_("Full", &i__5, &n, &afac[1], &ldab, &ainv[1], 
				&ldab);
			dpbt01_(uplo, &n, &kd, &a[1], &ldab, &ainv[1], &ldab, 
				&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___40.ciunit = *nout;
			    s_wsfe(&io___40);
			    do_fio(&c__1, uplo, (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 *)&nb, (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(
				    doublereal));
			    e_wsfe();
			    ++nfail;
			}
			++nrun;

/*                    Only do other tests if this is the first blocksize. */

			if (inb > 1) {
			    goto L50;
			}

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

			dlaset_("Full", &n, &n, &c_b50, &c_b51, &ainv[1], &
				lda);
			s_copy(srnamc_1.srnamt, "DPBTRS", (ftnlen)6, (ftnlen)
				6);
			dpbtrs_(uplo, &n, &kd, &n, &afac[1], &ldab, &ainv[1], 
				&lda, &info);

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

			anorm = dlansb_("1", uplo, &n, &kd, &a[1], &ldab, &
				rwork[1]);
			ainvnm = dlange_("1", &n, &n, &ainv[1], &lda, &rwork[
				1]);
			if (anorm <= 0. || ainvnm <= 0.) {
			    rcondc = 1.;
			} else {
			    rcondc = 1. / anorm / ainvnm;
			}

			i__5 = *nns;
			for (irhs = 1; irhs <= i__5; ++irhs) {
			    nrhs = nsval[irhs];

/* +    TEST 2   
                      Solve and compute residual for A * X = B. */

			    s_copy(srnamc_1.srnamt, "DLARHS", (ftnlen)6, (
				    ftnlen)6);
			    dlarhs_(path, xtype, uplo, " ", &n, &n, &kd, &kd, 
				    &nrhs, &a[1], &ldab, &xact[1], &lda, &b[1]
				    , &lda, iseed, &info);
			    dlacpy_("Full", &n, &nrhs, &b[1], &lda, &x[1], &
				    lda);

			    s_copy(srnamc_1.srnamt, "DPBTRS", (ftnlen)6, (
				    ftnlen)6);
			    dpbtrs_(uplo, &n, &kd, &nrhs, &afac[1], &ldab, &x[
				    1], &lda, &info);

/*                    Check error code from DPBTRS. */

			    if (info != 0) {
				alaerh_(path, "DPBTRS", &info, &c__0, uplo, &
					n, &n, &kd, &kd, &nrhs, &imat, &nfail,
					 &nerrs, nout);
			    }

			    dlacpy_("Full", &n, &nrhs, &b[1], &lda, &work[1], 
				    &lda);
			    dpbt02_(uplo, &n, &kd, &nrhs, &a[1], &ldab, &x[1],
				     &lda, &work[1], &lda, &rwork[1], &result[
				    1]);

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

			    dget04_(&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, "DPBRFS", (ftnlen)6, (
				    ftnlen)6);
			    dpbrfs_(uplo, &n, &kd, &nrhs, &a[1], &ldab, &afac[
				    1], &ldab, &b[1], &lda, &x[1], &lda, &
				    rwork[1], &rwork[nrhs + 1], &work[1], &
				    iwork[1], &info);

/*                    Check error code from DPBRFS. */

			    if (info != 0) {
				alaerh_(path, "DPBRFS", &info, &c__0, uplo, &
					n, &n, &kd, &kd, &nrhs, &imat, &nfail,
					 &nerrs, nout);
			    }

			    dget04_(&n, &nrhs, &x[1], &lda, &xact[1], &lda, &
				    rcondc, &result[3]);
			    dpbt05_(uplo, &n, &kd, &nrhs, &a[1], &ldab, &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___46.ciunit = *nout;
				    s_wsfe(&io___46);
				    do_fio(&c__1, uplo, (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;
				}
/* L30: */
			    }
			    nrun += 5;
/* L40: */
			}

/* +    TEST 7   
                      Get an estimate of RCOND = 1/CNDNUM. */

			s_copy(srnamc_1.srnamt, "DPBCON", (ftnlen)6, (ftnlen)
				6);
			dpbcon_(uplo, &n, &kd, &afac[1], &ldab, &anorm, &
				rcond, &work[1], &iwork[1], &info);

/*                    Check error code from DPBCON. */

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

			result[6] = dget06_(&rcond, &rcondc);

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

			if (result[6] >= *thresh) {
			    if (nfail == 0 && nerrs == 0) {
				alahd_(nout, path);
			    }
			    io___48.ciunit = *nout;
			    s_wsfe(&io___48);
			    do_fio(&c__1, uplo, (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;
			}
			++nrun;
L50:
			;
		    }
L60:
		    ;
		}
/* L70: */
	    }
/* L80: */
	}
/* L90: */
    }

/*     Print a summary of the results. */

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

    return 0;

/*     End of DCHKPB */

} /* dchkpb_ */
Exemplo n.º 4
0
/* Subroutine */ int derrpo_(char *path, integer *nunit)
{
    /* Builtin functions */
    integer s_wsle(cilist *), e_wsle(void);
    /* Subroutine */ int s_copy(char *, char *, ftnlen, ftnlen);

    /* Local variables */
    doublereal a[16]	/* was [4][4] */, b[4];
    integer i__, j;
    doublereal w[12], x[4];
    char c2[2];
    doublereal r1[4], r2[4], af[16]	/* was [4][4] */;
    integer iw[4], info;
    doublereal anrm, rcond;
    extern /* Subroutine */ int dpbtf2_(char *, integer *, integer *, 
	    doublereal *, integer *, integer *), dpotf2_(char *, 
	    integer *, doublereal *, integer *, integer *), alaesm_(
	    char *, logical *, integer *), dpbcon_(char *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, integer *, integer *);
    extern logical lsamen_(integer *, char *, char *);
    extern /* Subroutine */ int dpbequ_(char *, integer *, integer *, 
	    doublereal *, integer *, doublereal *, doublereal *, doublereal *, 
	     integer *), dpbrfs_(char *, integer *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, integer *, 
	    doublereal *, integer *, doublereal *, integer *, doublereal *, 
	    doublereal *, doublereal *, integer *, integer *), 
	    dpbtrf_(char *, integer *, integer *, doublereal *, integer *, 
	    integer *), dpocon_(char *, integer *, doublereal *, 
	    integer *, doublereal *, doublereal *, doublereal *, integer *, 
	    integer *), chkxer_(char *, integer *, integer *, logical 
	    *, logical *), dppcon_(char *, integer *, doublereal *, 
	    doublereal *, doublereal *, doublereal *, integer *, integer *), dpoequ_(integer *, doublereal *, integer *, doublereal *, 
	     doublereal *, doublereal *, integer *), dpbtrs_(char *, integer *
, integer *, integer *, doublereal *, integer *, doublereal *, 
	    integer *, integer *), dporfs_(char *, integer *, integer 
	    *, doublereal *, integer *, doublereal *, integer *, doublereal *, 
	     integer *, doublereal *, integer *, doublereal *, doublereal *, 
	    doublereal *, integer *, integer *), dpotrf_(char *, 
	    integer *, doublereal *, integer *, integer *), dpotri_(
	    char *, integer *, doublereal *, integer *, integer *), 
	    dppequ_(char *, integer *, doublereal *, doublereal *, doublereal 
	    *, doublereal *, integer *), dpprfs_(char *, integer *, 
	    integer *, doublereal *, doublereal *, doublereal *, integer *, 
	    doublereal *, integer *, doublereal *, doublereal *, doublereal *, 
	     integer *, integer *), dpptrf_(char *, integer *, 
	    doublereal *, integer *), dpptri_(char *, integer *, 
	    doublereal *, integer *), dpotrs_(char *, integer *, 
	    integer *, doublereal *, integer *, doublereal *, integer *, 
	    integer *), dpptrs_(char *, integer *, integer *, 
	    doublereal *, doublereal *, integer *, integer *);

    /* Fortran I/O blocks */
    static cilist io___1 = { 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 .. */
/*     .. */

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

/*  DERRPO tests the error exits for the DOUBLE PRECISION routines */
/*  for symmetric positive definite matrices. */

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

/*  PATH    (input) CHARACTER*3 */
/*          The LAPACK path name for the routines to be tested. */

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

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

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

    infoc_1.nout = *nunit;
    io___1.ciunit = infoc_1.nout;
    s_wsle(&io___1);
    e_wsle();
    s_copy(c2, path + 1, (ftnlen)2, (ftnlen)2);

/*     Set the variables to innocuous values. */

    for (j = 1; j <= 4; ++j) {
	for (i__ = 1; i__ <= 4; ++i__) {
	    a[i__ + (j << 2) - 5] = 1. / (doublereal) (i__ + j);
	    af[i__ + (j << 2) - 5] = 1. / (doublereal) (i__ + j);
/* L10: */
	}
	b[j - 1] = 0.;
	r1[j - 1] = 0.;
	r2[j - 1] = 0.;
	w[j - 1] = 0.;
	x[j - 1] = 0.;
	iw[j - 1] = j;
/* L20: */
    }
    infoc_1.ok = TRUE_;

    if (lsamen_(&c__2, c2, "PO")) {

/*        Test error exits of the routines that use the Cholesky */
/*        decomposition of a symmetric positive definite matrix. */

/*        DPOTRF */

	s_copy(srnamc_1.srnamt, "DPOTRF", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpotrf_("/", &c__0, a, &c__1, &info);
	chkxer_("DPOTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpotrf_("U", &c_n1, a, &c__1, &info);
	chkxer_("DPOTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 4;
	dpotrf_("U", &c__2, a, &c__1, &info);
	chkxer_("DPOTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPOTF2 */

	s_copy(srnamc_1.srnamt, "DPOTF2", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpotf2_("/", &c__0, a, &c__1, &info);
	chkxer_("DPOTF2", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpotf2_("U", &c_n1, a, &c__1, &info);
	chkxer_("DPOTF2", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 4;
	dpotf2_("U", &c__2, a, &c__1, &info);
	chkxer_("DPOTF2", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPOTRI */

	s_copy(srnamc_1.srnamt, "DPOTRI", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpotri_("/", &c__0, a, &c__1, &info);
	chkxer_("DPOTRI", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpotri_("U", &c_n1, a, &c__1, &info);
	chkxer_("DPOTRI", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 4;
	dpotri_("U", &c__2, a, &c__1, &info);
	chkxer_("DPOTRI", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPOTRS */

	s_copy(srnamc_1.srnamt, "DPOTRS", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpotrs_("/", &c__0, &c__0, a, &c__1, b, &c__1, &info);
	chkxer_("DPOTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpotrs_("U", &c_n1, &c__0, a, &c__1, b, &c__1, &info);
	chkxer_("DPOTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpotrs_("U", &c__0, &c_n1, a, &c__1, b, &c__1, &info);
	chkxer_("DPOTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 5;
	dpotrs_("U", &c__2, &c__1, a, &c__1, b, &c__2, &info);
	chkxer_("DPOTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 7;
	dpotrs_("U", &c__2, &c__1, a, &c__2, b, &c__1, &info);
	chkxer_("DPOTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPORFS */

	s_copy(srnamc_1.srnamt, "DPORFS", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dporfs_("/", &c__0, &c__0, a, &c__1, af, &c__1, b, &c__1, x, &c__1, 
		r1, r2, w, iw, &info);
	chkxer_("DPORFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dporfs_("U", &c_n1, &c__0, a, &c__1, af, &c__1, b, &c__1, x, &c__1, 
		r1, r2, w, iw, &info);
	chkxer_("DPORFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dporfs_("U", &c__0, &c_n1, a, &c__1, af, &c__1, b, &c__1, x, &c__1, 
		r1, r2, w, iw, &info);
	chkxer_("DPORFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 5;
	dporfs_("U", &c__2, &c__1, a, &c__1, af, &c__2, b, &c__2, x, &c__2, 
		r1, r2, w, iw, &info);
	chkxer_("DPORFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 7;
	dporfs_("U", &c__2, &c__1, a, &c__2, af, &c__1, b, &c__2, x, &c__2, 
		r1, r2, w, iw, &info);
	chkxer_("DPORFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 9;
	dporfs_("U", &c__2, &c__1, a, &c__2, af, &c__2, b, &c__1, x, &c__2, 
		r1, r2, w, iw, &info);
	chkxer_("DPORFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 11;
	dporfs_("U", &c__2, &c__1, a, &c__2, af, &c__2, b, &c__2, x, &c__1, 
		r1, r2, w, iw, &info);
	chkxer_("DPORFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPOCON */

	s_copy(srnamc_1.srnamt, "DPOCON", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpocon_("/", &c__0, a, &c__1, &anrm, &rcond, w, iw, &info);
	chkxer_("DPOCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpocon_("U", &c_n1, a, &c__1, &anrm, &rcond, w, iw, &info);
	chkxer_("DPOCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 4;
	dpocon_("U", &c__2, a, &c__1, &anrm, &rcond, w, iw, &info);
	chkxer_("DPOCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPOEQU */

	s_copy(srnamc_1.srnamt, "DPOEQU", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpoequ_(&c_n1, a, &c__1, r1, &rcond, &anrm, &info);
	chkxer_("DPOEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpoequ_(&c__2, a, &c__1, r1, &rcond, &anrm, &info);
	chkxer_("DPOEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

    } else if (lsamen_(&c__2, c2, "PP")) {

/*        Test error exits of the routines that use the Cholesky */
/*        decomposition of a symmetric positive definite packed matrix. */

/*        DPPTRF */

	s_copy(srnamc_1.srnamt, "DPPTRF", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpptrf_("/", &c__0, a, &info);
	chkxer_("DPPTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpptrf_("U", &c_n1, a, &info);
	chkxer_("DPPTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPPTRI */

	s_copy(srnamc_1.srnamt, "DPPTRI", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpptri_("/", &c__0, a, &info);
	chkxer_("DPPTRI", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpptri_("U", &c_n1, a, &info);
	chkxer_("DPPTRI", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPPTRS */

	s_copy(srnamc_1.srnamt, "DPPTRS", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpptrs_("/", &c__0, &c__0, a, b, &c__1, &info);
	chkxer_("DPPTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpptrs_("U", &c_n1, &c__0, a, b, &c__1, &info);
	chkxer_("DPPTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpptrs_("U", &c__0, &c_n1, a, b, &c__1, &info);
	chkxer_("DPPTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 6;
	dpptrs_("U", &c__2, &c__1, a, b, &c__1, &info);
	chkxer_("DPPTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPPRFS */

	s_copy(srnamc_1.srnamt, "DPPRFS", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpprfs_("/", &c__0, &c__0, a, af, b, &c__1, x, &c__1, r1, r2, w, iw, &
		info);
	chkxer_("DPPRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpprfs_("U", &c_n1, &c__0, a, af, b, &c__1, x, &c__1, r1, r2, w, iw, &
		info);
	chkxer_("DPPRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpprfs_("U", &c__0, &c_n1, a, af, b, &c__1, x, &c__1, r1, r2, w, iw, &
		info);
	chkxer_("DPPRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 7;
	dpprfs_("U", &c__2, &c__1, a, af, b, &c__1, x, &c__2, r1, r2, w, iw, &
		info);
	chkxer_("DPPRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 9;
	dpprfs_("U", &c__2, &c__1, a, af, b, &c__2, x, &c__1, r1, r2, w, iw, &
		info);
	chkxer_("DPPRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPPCON */

	s_copy(srnamc_1.srnamt, "DPPCON", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dppcon_("/", &c__0, a, &anrm, &rcond, w, iw, &info);
	chkxer_("DPPCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dppcon_("U", &c_n1, a, &anrm, &rcond, w, iw, &info);
	chkxer_("DPPCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPPEQU */

	s_copy(srnamc_1.srnamt, "DPPEQU", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dppequ_("/", &c__0, a, r1, &rcond, &anrm, &info);
	chkxer_("DPPEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dppequ_("U", &c_n1, a, r1, &rcond, &anrm, &info);
	chkxer_("DPPEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

    } else if (lsamen_(&c__2, c2, "PB")) {

/*        Test error exits of the routines that use the Cholesky */
/*        decomposition of a symmetric positive definite band matrix. */

/*        DPBTRF */

	s_copy(srnamc_1.srnamt, "DPBTRF", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpbtrf_("/", &c__0, &c__0, a, &c__1, &info);
	chkxer_("DPBTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpbtrf_("U", &c_n1, &c__0, a, &c__1, &info);
	chkxer_("DPBTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpbtrf_("U", &c__1, &c_n1, a, &c__1, &info);
	chkxer_("DPBTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 5;
	dpbtrf_("U", &c__2, &c__1, a, &c__1, &info);
	chkxer_("DPBTRF", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPBTF2 */

	s_copy(srnamc_1.srnamt, "DPBTF2", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpbtf2_("/", &c__0, &c__0, a, &c__1, &info);
	chkxer_("DPBTF2", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpbtf2_("U", &c_n1, &c__0, a, &c__1, &info);
	chkxer_("DPBTF2", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpbtf2_("U", &c__1, &c_n1, a, &c__1, &info);
	chkxer_("DPBTF2", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 5;
	dpbtf2_("U", &c__2, &c__1, a, &c__1, &info);
	chkxer_("DPBTF2", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPBTRS */

	s_copy(srnamc_1.srnamt, "DPBTRS", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpbtrs_("/", &c__0, &c__0, &c__0, a, &c__1, b, &c__1, &info);
	chkxer_("DPBTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpbtrs_("U", &c_n1, &c__0, &c__0, a, &c__1, b, &c__1, &info);
	chkxer_("DPBTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpbtrs_("U", &c__1, &c_n1, &c__0, a, &c__1, b, &c__1, &info);
	chkxer_("DPBTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 4;
	dpbtrs_("U", &c__0, &c__0, &c_n1, a, &c__1, b, &c__1, &info);
	chkxer_("DPBTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 6;
	dpbtrs_("U", &c__2, &c__1, &c__1, a, &c__1, b, &c__1, &info);
	chkxer_("DPBTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 8;
	dpbtrs_("U", &c__2, &c__0, &c__1, a, &c__1, b, &c__1, &info);
	chkxer_("DPBTRS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPBRFS */

	s_copy(srnamc_1.srnamt, "DPBRFS", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpbrfs_("/", &c__0, &c__0, &c__0, a, &c__1, af, &c__1, b, &c__1, x, &
		c__1, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpbrfs_("U", &c_n1, &c__0, &c__0, a, &c__1, af, &c__1, b, &c__1, x, &
		c__1, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpbrfs_("U", &c__1, &c_n1, &c__0, a, &c__1, af, &c__1, b, &c__1, x, &
		c__1, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 4;
	dpbrfs_("U", &c__0, &c__0, &c_n1, a, &c__1, af, &c__1, b, &c__1, x, &
		c__1, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 6;
	dpbrfs_("U", &c__2, &c__1, &c__1, a, &c__1, af, &c__2, b, &c__2, x, &
		c__2, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 8;
	dpbrfs_("U", &c__2, &c__1, &c__1, a, &c__2, af, &c__1, b, &c__2, x, &
		c__2, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 10;
	dpbrfs_("U", &c__2, &c__0, &c__1, a, &c__1, af, &c__1, b, &c__1, x, &
		c__2, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 12;
	dpbrfs_("U", &c__2, &c__0, &c__1, a, &c__1, af, &c__1, b, &c__2, x, &
		c__1, r1, r2, w, iw, &info);
	chkxer_("DPBRFS", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPBCON */

	s_copy(srnamc_1.srnamt, "DPBCON", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpbcon_("/", &c__0, &c__0, a, &c__1, &anrm, &rcond, w, iw, &info);
	chkxer_("DPBCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpbcon_("U", &c_n1, &c__0, a, &c__1, &anrm, &rcond, w, iw, &info);
	chkxer_("DPBCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpbcon_("U", &c__1, &c_n1, a, &c__1, &anrm, &rcond, w, iw, &info);
	chkxer_("DPBCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 5;
	dpbcon_("U", &c__2, &c__1, a, &c__1, &anrm, &rcond, w, iw, &info);
	chkxer_("DPBCON", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);

/*        DPBEQU */

	s_copy(srnamc_1.srnamt, "DPBEQU", (ftnlen)32, (ftnlen)6);
	infoc_1.infot = 1;
	dpbequ_("/", &c__0, &c__0, a, &c__1, r1, &rcond, &anrm, &info);
	chkxer_("DPBEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 2;
	dpbequ_("U", &c_n1, &c__0, a, &c__1, r1, &rcond, &anrm, &info);
	chkxer_("DPBEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 3;
	dpbequ_("U", &c__1, &c_n1, a, &c__1, r1, &rcond, &anrm, &info);
	chkxer_("DPBEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
	infoc_1.infot = 5;
	dpbequ_("U", &c__2, &c__1, a, &c__1, r1, &rcond, &anrm, &info);
	chkxer_("DPBEQU", &infoc_1.infot, &infoc_1.nout, &infoc_1.lerr, &
		infoc_1.ok);
    }

/*     Print a summary line. */

    alaesm_(path, &infoc_1.ok, &infoc_1.nout);

    return 0;

/*     End of DERRPO */

} /* derrpo_ */