derrab.f

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*> \brief \b DERRAB
*
*  =========== DOCUMENTATION ===========
*
* Online html documentation available at
*            http://www.netlib.org/lapack/explore-html/
*
*  Definition:
*  ===========
*
*       SUBROUTINE DERRAB( NUNIT )
*
*       .. Scalar Arguments ..
*       INTEGER            NUNIT
*       ..
*
*
*> \par Purpose:
*  =============
*>
*> \verbatim
*>
*> DERRAB tests the error exits for DSGESV.
*> \endverbatim
*
*  Arguments:
*  ==========
*
*> \param[in] NUNIT
*> \verbatim
*>          NUNIT is INTEGER
*>          The unit number for output.
*> \endverbatim
*
*  Authors:
*  ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \ingroup double_lin
*
*  =====================================================================
      SUBROUTINE derrab( NUNIT )
*
*  -- LAPACK test routine --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. Scalar Arguments ..
      INTEGER            NUNIT
*     ..
*
*  =====================================================================
*
*     .. Parameters ..
      INTEGER            NMAX
      parameter( nmax = 4 )
*     ..
*     .. Local Scalars ..
      INTEGER            I, INFO, ITER, J
*     ..
*     .. Local Arrays ..
      INTEGER            IP( NMAX )
      DOUBLE PRECISION   A( NMAX, NMAX ), AF( NMAX, NMAX ), B( NMAX ),
     $                   C( NMAX ), R( NMAX ), R1( NMAX ), R2( NMAX ),
     $                   W( 2*NMAX ), X( NMAX )
      DOUBLE PRECISION   WORK(1)
      REAL               SWORK(1)
*     ..
*     .. External Subroutines ..
      EXTERNAL           chkxer, dsgesv
*     ..
*     .. Scalars in Common ..
      LOGICAL            LERR, OK
      CHARACTER*32       SRNAMT
      INTEGER            INFOT, NOUT
*     ..
*     .. Common blocks ..
      COMMON             / infoc / infot, nout, ok, lerr
      COMMON             / srnamc / srnamt
*     ..
*     .. Intrinsic Functions ..
      INTRINSIC          dble
*     ..
*     .. Executable Statements ..
*
      nout = nunit
      WRITE( nout, fmt = * )
*
*     Set the variables to innocuous values.
*
      DO 20 j = 1, nmax
         DO 10 i = 1, nmax
            a( i, j ) = 1.d0 / dble( i+j )
            af( i, j ) = 1.d0 / dble( i+j )
   10    CONTINUE
         b( j ) = 0.d0
         r1( j ) = 0.d0
         r2( j ) = 0.d0
         w( j ) = 0.d0
         x( j ) = 0.d0
         c( j ) = 0.d0
         r( j ) = 0.d0
         ip( j ) = j
   20 CONTINUE
      ok = .true.
*
      srnamt = 'DSGESV'
      infot = 1
      CALL dsgesv(-1,0,a,1,ip,b,1,x,1,work,swork,iter,info)
      CALL chkxer( 'DSGESV', infot, nout, lerr, ok )
      infot = 2
      CALL dsgesv(0,-1,a,1,ip,b,1,x,1,work,swork,iter,info)
      CALL chkxer( 'DSGESV', infot, nout, lerr, ok )
      infot = 4
      CALL dsgesv(2,1,a,1,ip,b,2,x,2,work,swork,iter,info)
      CALL chkxer( 'DSGESV', infot, nout, lerr, ok )
      infot = 7
      CALL dsgesv(2,1,a,2,ip,b,1,x,2,work,swork,iter,info)
      CALL chkxer( 'DSGESV', infot, nout, lerr, ok )
      infot = 9
      CALL dsgesv(2,1,a,2,ip,b,2,x,1,work,swork,iter,info)
      CALL chkxer( 'DSGESV', infot, nout, lerr, ok )
*
*     Print a summary line.
*
      IF( ok ) THEN
         WRITE( nout, fmt = 9999 )'DSGESV'
      ELSE
         WRITE( nout, fmt = 9998 )'DSGESV'
      END IF
*
 9999 FORMAT( 1x, a6, ' drivers passed the tests of the error exits' )
 9998 FORMAT( ' *** ', a6, ' drivers failed the tests of the error ',
     $      'exits ***' )
*
      RETURN
*
*     End of DERRAB
*
      END