      SUBROUTINE DDRVRF1( NOUT, NN, NVAL, THRESH, A, LDA, ARF, WORK )
*
*  -- LAPACK test routine (version 3.2.0) --
*     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
*     November 2008
*
*     .. Scalar Arguments ..
      INTEGER            LDA, NN, NOUT
      DOUBLE PRECISION   THRESH
*     ..
*     .. Array Arguments ..
      INTEGER            NVAL( NN )
      DOUBLE PRECISION   A( LDA, * ), ARF( * ), WORK( * )
*     ..
*
*  Purpose
*  =======
*
*  DDRVRF1 tests the LAPACK RFP routines:
*      DLANSF
*
*  Arguments
*  =========
*
*  NOUT          (input) INTEGER
*                The unit number for output.
*
*  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) 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.
*
*  A             (workspace) DOUBLE PRECISION array, dimension (LDA,NMAX)
*
*  LDA           (input) INTEGER
*                The leading dimension of the array A.  LDA >= max(1,NMAX).
*
*  ARF           (workspace) DOUBLE PRECISION array, dimension ((NMAX*(NMAX+1))/2).
*
*  WORK          (workspace) DOUBLE PRECISION array, dimension ( NMAX )
*
*  =====================================================================
*     ..
*     .. Parameters ..
      DOUBLE PRECISION   ONE
      PARAMETER          ( ONE = 1.0D+0 )
      INTEGER            NTESTS
      PARAMETER          ( NTESTS = 1 )
*     ..
*     .. Local Scalars ..
      CHARACTER          UPLO, CFORM, NORM
      INTEGER            I, IFORM, IIN, IIT, INFO, INORM, IUPLO, J, N,
     +                   NERRS, NFAIL, NRUN
      DOUBLE PRECISION   EPS, LARGE, NORMA, NORMARF, SMALL
*     ..
*     .. Local Arrays ..
      CHARACTER          UPLOS( 2 ), FORMS( 2 ), NORMS( 4 )
      INTEGER            ISEED( 4 ), ISEEDY( 4 )
      DOUBLE PRECISION   RESULT( NTESTS )
*     ..
*     .. External Functions ..
      DOUBLE PRECISION   DLAMCH, DLANSY, DLANSF, DLARND
      EXTERNAL           DLAMCH, DLANSY, DLANSF, DLARND
*     ..
*     .. External Subroutines ..
      EXTERNAL           DTRTTF
*     ..
*     .. Scalars in Common ..
      CHARACTER*32       SRNAMT
*     ..
*     .. Common blocks ..
      COMMON             / SRNAMC / SRNAMT
*     ..
*     .. Data statements ..
      DATA               ISEEDY / 1988, 1989, 1990, 1991 /
      DATA               UPLOS / 'U', 'L' /
      DATA               FORMS / 'N', 'T' /
      DATA               NORMS / 'M', '1', 'I', 'F' /
*     ..
*     .. Executable Statements ..
*
*     Initialize constants and the random number seed.
*
      NRUN = 0
      NFAIL = 0
      NERRS = 0
      INFO = 0
      DO 10 I = 1, 4
         ISEED( I ) = ISEEDY( I )
   10 CONTINUE
*
      EPS = DLAMCH( 'Precision' )
      SMALL = DLAMCH( 'Safe minimum' )
      LARGE = ONE / SMALL
      SMALL = SMALL * LDA * LDA 
      LARGE = LARGE / LDA / LDA
*
      DO 130 IIN = 1, NN
*
         N = NVAL( IIN )
*
         DO 120 IIT = 1, 3
*
*           IIT = 1 : random matrix
*           IIT = 2 : random matrix scaled near underflow
*           IIT = 3 : random matrix scaled near overflow
*
            DO J = 1, N
               DO I = 1, N
                  A( I, J) = DLARND( 2, ISEED )
               END DO
            END DO
*
            IF ( IIT.EQ.2 ) THEN
               DO J = 1, N
                  DO I = 1, N
                     A( I, J) = A( I, J ) * LARGE
                  END DO
               END DO
            END IF
*
            IF ( IIT.EQ.3 ) THEN
               DO J = 1, N
                  DO I = 1, N
                     A( I, J) = A( I, J) * SMALL
                  END DO
               END DO
            END IF
*
*           Do first for UPLO = 'U', then for UPLO = 'L'
*
            DO 110 IUPLO = 1, 2
*
               UPLO = UPLOS( IUPLO )
*
*              Do first for CFORM = 'N', then for CFORM = 'C'
*
               DO 100 IFORM = 1, 2
*
                  CFORM = FORMS( IFORM )
*
                  SRNAMT = 'DTRTTF'
                  CALL DTRTTF( CFORM, UPLO, N, A, LDA, ARF, INFO )
*
*                 Check error code from DTRTTF
*
                  IF( INFO.NE.0 ) THEN
                     IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 ) THEN
                        WRITE( NOUT, * )
                        WRITE( NOUT, FMT = 9999 )
                     END IF
                     WRITE( NOUT, FMT = 9998 ) SRNAMT, UPLO, CFORM, N
                     NERRS = NERRS + 1
                     GO TO 100
                  END IF
*
                  DO 90 INORM = 1, 4
*
*                    Check all four norms: 'M', '1', 'I', 'F'
*
                     NORM = NORMS( INORM )
                     NORMARF = DLANSF( NORM, CFORM, UPLO, N, ARF, WORK )
                     NORMA = DLANSY( NORM, UPLO, N, A, LDA, WORK )
*
                     RESULT(1) = ( NORMA - NORMARF ) / NORMA / EPS
                     NRUN = NRUN + 1
*
                     IF( RESULT(1).GE.THRESH ) THEN
                        IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 ) THEN
                           WRITE( NOUT, * )
                           WRITE( NOUT, FMT = 9999 )
                        END IF
                        WRITE( NOUT, FMT = 9997 ) 'DLANSF', 
     +                      N, IIT, UPLO, CFORM, NORM, RESULT(1)
                        NFAIL = NFAIL + 1
                     END IF
   90             CONTINUE
  100          CONTINUE
  110       CONTINUE
  120    CONTINUE
  130 CONTINUE
*
*     Print a summary of the results.
*
      IF ( NFAIL.EQ.0 ) THEN
         WRITE( NOUT, FMT = 9996 ) 'DLANSF', NRUN
      ELSE
         WRITE( NOUT, FMT = 9995 ) 'DLANSF', NFAIL, NRUN
      END IF
      IF ( NERRS.NE.0 ) THEN
         WRITE( NOUT, FMT = 9994 ) NERRS, 'DLANSF'
      END IF
*
 9999 FORMAT( 1X, ' *** Error(s) or Failure(s) while testing DLANSF
     +         ***')
 9998 FORMAT( 1X, '     Error in ',A6,' with UPLO=''',A1,''', FORM=''',
     +        A1,''', N=',I5)
 9997 FORMAT( 1X, '     Failure in ',A6,' N=',I5,' TYPE=',I5,' UPLO=''',
     +        A1, ''', FORM =''',A1,''', NORM=''',A1,''', test=',G12.5)
 9996 FORMAT( 1X, 'All tests for ',A6,' auxiliary routine passed the ',
     +        'threshold (',I5,' tests run)')
 9995 FORMAT( 1X, A6, ' auxiliary routine:',I5,' out of ',I5,
     +        ' tests failed to pass the threshold')
 9994 FORMAT( 26X, I5,' error message recorded (',A6,')')
*
      RETURN
*
*     End of DDRVRF1
*
      END
