schktb.f

来自「famous linear algebra library (LAPACK) p」· F 代码 · 共 488 行 · 第 1/2 页

      SUBROUTINE SCHKTB( DOTYPE, NN, NVAL, NNS, NSVAL, THRESH, TSTERR,
     $                   NMAX, AB, AINV, B, X, XACT, WORK, RWORK, IWORK,
     $                   NOUT )
*
*  -- LAPACK test routine (version 3.1) --
*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
*     November 2006
*
*     .. Scalar Arguments ..
      LOGICAL            TSTERR
      INTEGER            NMAX, NN, NNS, NOUT
      REAL               THRESH
*     ..
*     .. Array Arguments ..
      LOGICAL            DOTYPE( * )
      INTEGER            IWORK( * ), NSVAL( * ), NVAL( * )
      REAL               AB( * ), AINV( * ), B( * ), RWORK( * ),
     $                   WORK( * ), X( * ), XACT( * )
*     ..
*
*  Purpose
*  =======
*
*  SCHKTB tests STBTRS, -RFS, and -CON, and SLATBS.
*
*  Arguments
*  =========
*
*  DOTYPE  (input) LOGICAL array, dimension (NTYPES)
*          The matrix types to be used for testing.  Matrices of type j
*          (for 1 <= j <= NTYPES) are used for testing if DOTYPE(j) =
*          .TRUE.; if DOTYPE(j) = .FALSE., then type j is not used.
*
*  NN      (input) INTEGER
*          The number of values of N contained in the vector NVAL.
*
*  NVAL    (input) INTEGER array, dimension (NN)
*          The values of the matrix column dimension N.
*
*  NNS     (input) INTEGER
*          The number of values of NRHS contained in the vector NSVAL.
*
*  NSVAL   (input) INTEGER array, dimension (NNS)
*          The values of the number of right hand sides NRHS.
*
*  THRESH  (input) 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.
*
*  NMAX    (input) INTEGER
*          The leading dimension of the work arrays.
*          NMAX >= the maximum value of N in NVAL.
*
*  AB      (workspace) REAL array, dimension (NMAX*NMAX)
*
*  AINV    (workspace) REAL array, dimension (NMAX*NMAX)
*
*  B       (workspace) REAL array, dimension (NMAX*NSMAX)
*          where NSMAX is the largest entry in NSVAL.
*
*  X       (workspace) REAL array, dimension (NMAX*NSMAX)
*
*  XACT    (workspace) REAL array, dimension (NMAX*NSMAX)
*
*  WORK    (workspace) REAL 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.
*
*  =====================================================================
*
*     .. Parameters ..
      INTEGER            NTYPE1, NTYPES
      PARAMETER          ( NTYPE1 = 9, NTYPES = 17 )
      INTEGER            NTESTS
      PARAMETER          ( NTESTS = 8 )
      INTEGER            NTRAN
      PARAMETER          ( NTRAN = 3 )
      REAL               ONE, ZERO
      PARAMETER          ( ONE = 1.0E+0, ZERO = 0.0E+0 )
*     ..
*     .. Local Scalars ..
      CHARACTER          DIAG, NORM, TRANS, UPLO, XTYPE
      CHARACTER*3        PATH
      INTEGER            I, IDIAG, IK, IMAT, IN, INFO, IRHS, ITRAN,
     $                   IUPLO, J, K, KD, LDA, LDAB, N, NERRS, NFAIL,
     $                   NIMAT, NIMAT2, NK, NRHS, NRUN
      REAL               AINVNM, ANORM, RCOND, RCONDC, RCONDI, RCONDO,
     $                   SCALE
*     ..
*     .. Local Arrays ..
      CHARACTER          TRANSS( NTRAN ), UPLOS( 2 )
      INTEGER            ISEED( 4 ), ISEEDY( 4 )
      REAL               RESULT( NTESTS )
*     ..
*     .. External Functions ..
      LOGICAL            LSAME
      REAL               SLANTB, SLANTR
      EXTERNAL           LSAME, SLANTB, SLANTR
*     ..
*     .. External Subroutines ..
      EXTERNAL           ALAERH, ALAHD, ALASUM, SCOPY, SERRTR, SGET04,
     $                   SLACPY, SLARHS, SLASET, SLATBS, SLATTB, STBCON,
     $                   STBRFS, STBSV, STBT02, STBT03, STBT05, STBT06,
     $                   STBTRS
*     ..
*     .. Scalars in Common ..
      LOGICAL            LERR, OK
      CHARACTER*6        SRNAMT
      INTEGER            INFOT, IOUNIT
*     ..
*     .. Common blocks ..
      COMMON             / INFOC / INFOT, IOUNIT, OK, LERR
      COMMON             / SRNAMC / SRNAMT
*     ..
*     .. Intrinsic Functions ..
      INTRINSIC          MAX, MIN
*     ..
*     .. Data statements ..
      DATA               ISEEDY / 1988, 1989, 1990, 1991 /
      DATA               UPLOS / 'U', 'L' / , TRANSS / 'N', 'T', 'C' /
*     ..
*     .. Executable Statements ..
*
*     Initialize constants and the random number seed.
*
      PATH( 1: 1 ) = 'Single precision'
      PATH( 2: 3 ) = 'TB'
      NRUN = 0
      NFAIL = 0
      NERRS = 0
      DO 10 I = 1, 4
         ISEED( I ) = ISEEDY( I )
   10 CONTINUE
*
*     Test the error exits
*
      IF( TSTERR )
     $   CALL SERRTR( PATH, NOUT )
      INFOT = 0
*
      DO 140 IN = 1, NN
*
*        Do for each value of N in NVAL
*
         N = NVAL( IN )
         LDA = MAX( 1, N )
         XTYPE = 'N'
         NIMAT = NTYPE1
         NIMAT2 = NTYPES
         IF( N.LE.0 ) THEN
            NIMAT = 1
            NIMAT2 = NTYPE1 + 1
         END IF
*
         NK = MIN( N+1, 4 )
         DO 130 IK = 1, NK
*
*           Do for KD = 0, N, (3N-1)/4, and (N+1)/4. This order makes
*           it easier to skip redundant values for small values of N.
*
            IF( IK.EQ.1 ) THEN
               KD = 0
            ELSE IF( IK.EQ.2 ) THEN
               KD = MAX( N, 0 )
            ELSE IF( IK.EQ.3 ) THEN
               KD = ( 3*N-1 ) / 4
            ELSE IF( IK.EQ.4 ) THEN
               KD = ( N+1 ) / 4
            END IF
            LDAB = KD + 1
*
            DO 90 IMAT = 1, NIMAT
*
*              Do the tests only if DOTYPE( IMAT ) is true.
*
               IF( .NOT.DOTYPE( IMAT ) )
     $            GO TO 90
*
               DO 80 IUPLO = 1, 2
*
*                 Do first for UPLO = 'U', then for UPLO = 'L'
*
                  UPLO = UPLOS( IUPLO )
*
*                 Call SLATTB to generate a triangular test matrix.
*
                  SRNAMT = 'SLATTB'
                  CALL SLATTB( IMAT, UPLO, 'No transpose', DIAG, ISEED,
     $                         N, KD, AB, LDAB, X, WORK, INFO )
*
*                 Set IDIAG = 1 for non-unit matrices, 2 for unit.
*
                  IF( LSAME( DIAG, 'N' ) ) THEN
                     IDIAG = 1
                  ELSE
                     IDIAG = 2
                  END IF
*
*                 Form the inverse of A so we can get a good estimate
*                 of RCONDC = 1/(norm(A) * norm(inv(A))).
*
                  CALL SLASET( 'Full', N, N, ZERO, ONE, AINV, LDA )
                  IF( LSAME( UPLO, 'U' ) ) THEN
                     DO 20 J = 1, N
                        CALL STBSV( UPLO, 'No transpose', DIAG, J, KD,
     $                              AB, LDAB, AINV( ( J-1 )*LDA+1 ), 1 )
   20                CONTINUE
                  ELSE
                     DO 30 J = 1, N
                        CALL STBSV( UPLO, 'No transpose', DIAG, N-J+1,
     $                              KD, AB( ( J-1 )*LDAB+1 ), LDAB,
     $                              AINV( ( J-1 )*LDA+J ), 1 )
   30                CONTINUE
                  END IF
*
*                 Compute the 1-norm condition number of A.
*
                  ANORM = SLANTB( '1', UPLO, DIAG, N, KD, AB, LDAB,
     $                    RWORK )
                  AINVNM = SLANTR( '1', UPLO, DIAG, N, N, AINV, LDA,
     $                     RWORK )
                  IF( ANORM.LE.ZERO .OR. AINVNM.LE.ZERO ) THEN
                     RCONDO = ONE
                  ELSE
                     RCONDO = ( ONE / ANORM ) / AINVNM
                  END IF
*
*                 Compute the infinity-norm condition number of A.
*
                  ANORM = SLANTB( 'I', UPLO, DIAG, N, KD, AB, LDAB,
     $                    RWORK )
                  AINVNM = SLANTR( 'I', UPLO, DIAG, N, N, AINV, LDA,
     $                     RWORK )