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version 1.4, 2010/12/21 13:53:28 version 1.17, 2023/08/07 08:38:52
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       DOUBLE PRECISION FUNCTION DLA_GERCOND ( TRANS, N, A, LDA, AF,  *> \brief \b DLA_GERCOND estimates the Skeel condition number for a general matrix.
      $                                        LDAF, IPIV, CMODE, C,  
      $                                        INFO, WORK, IWORK )  
 *  
 *     -- LAPACK routine (version 3.2.1)                                 --  
 *     -- Contributed by James Demmel, Deaglan Halligan, Yozo Hida and --  
 *     -- Jason Riedy of Univ. of California Berkeley.                 --  
 *     -- April 2009                                                   --  
 *  *
 *     -- LAPACK is a software package provided by Univ. of Tennessee, --  *  =========== DOCUMENTATION ===========
 *     -- Univ. of California Berkeley and NAG Ltd.                    --  *
   * Online html documentation available at
   *            http://www.netlib.org/lapack/explore-html/
   *
   *> \htmlonly
   *> Download DLA_GERCOND + dependencies
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dla_gercond.f">
   *> [TGZ]</a>
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dla_gercond.f">
   *> [ZIP]</a>
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dla_gercond.f">
   *> [TXT]</a>
   *> \endhtmlonly
   *
   *  Definition:
   *  ===========
   *
   *       DOUBLE PRECISION FUNCTION DLA_GERCOND( TRANS, N, A, LDA, AF,
   *                                              LDAF, IPIV, CMODE, C,
   *                                              INFO, WORK, IWORK )
   *
   *       .. Scalar Arguments ..
   *       CHARACTER          TRANS
   *       INTEGER            N, LDA, LDAF, INFO, CMODE
   *       ..
   *       .. Array Arguments ..
   *       INTEGER            IPIV( * ), IWORK( * )
   *       DOUBLE PRECISION   A( LDA, * ), AF( LDAF, * ), WORK( * ),
   *      $                   C( * )
   *       ..
   *
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *>    DLA_GERCOND estimates the Skeel condition number of op(A) * op2(C)
   *>    where op2 is determined by CMODE as follows
   *>    CMODE =  1    op2(C) = C
   *>    CMODE =  0    op2(C) = I
   *>    CMODE = -1    op2(C) = inv(C)
   *>    The Skeel condition number cond(A) = norminf( |inv(A)||A| )
   *>    is computed by computing scaling factors R such that
   *>    diag(R)*A*op2(C) is row equilibrated and computing the standard
   *>    infinity-norm condition number.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] TRANS
   *> \verbatim
   *>          TRANS is 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 = Transpose)
   *> \endverbatim
   *>
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>     The number of linear equations, i.e., the order of the
   *>     matrix A.  N >= 0.
   *> \endverbatim
   *>
   *> \param[in] A
   *> \verbatim
   *>          A is DOUBLE PRECISION array, dimension (LDA,N)
   *>     On entry, the N-by-N matrix A.
   *> \endverbatim
   *>
   *> \param[in] LDA
   *> \verbatim
   *>          LDA is INTEGER
   *>     The leading dimension of the array A.  LDA >= max(1,N).
   *> \endverbatim
   *>
   *> \param[in] AF
   *> \verbatim
   *>          AF is DOUBLE PRECISION array, dimension (LDAF,N)
   *>     The factors L and U from the factorization
   *>     A = P*L*U as computed by DGETRF.
   *> \endverbatim
   *>
   *> \param[in] LDAF
   *> \verbatim
   *>          LDAF is INTEGER
   *>     The leading dimension of the array AF.  LDAF >= max(1,N).
   *> \endverbatim
   *>
   *> \param[in] IPIV
   *> \verbatim
   *>          IPIV is INTEGER array, dimension (N)
   *>     The pivot indices from the factorization A = P*L*U
   *>     as computed by DGETRF; row i of the matrix was interchanged
   *>     with row IPIV(i).
   *> \endverbatim
   *>
   *> \param[in] CMODE
   *> \verbatim
   *>          CMODE is INTEGER
   *>     Determines op2(C) in the formula op(A) * op2(C) as follows:
   *>     CMODE =  1    op2(C) = C
   *>     CMODE =  0    op2(C) = I
   *>     CMODE = -1    op2(C) = inv(C)
   *> \endverbatim
   *>
   *> \param[in] C
   *> \verbatim
   *>          C is DOUBLE PRECISION array, dimension (N)
   *>     The vector C in the formula op(A) * op2(C).
   *> \endverbatim
   *>
   *> \param[out] INFO
   *> \verbatim
   *>          INFO is INTEGER
   *>       = 0:  Successful exit.
   *>     i > 0:  The ith argument is invalid.
   *> \endverbatim
   *>
   *> \param[out] WORK
   *> \verbatim
   *>          WORK is DOUBLE PRECISION array, dimension (3*N).
   *>     Workspace.
   *> \endverbatim
   *>
   *> \param[out] IWORK
   *> \verbatim
   *>          IWORK is INTEGER array, dimension (N).
   *>     Workspace.
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee
   *> \author Univ. of California Berkeley
   *> \author Univ. of Colorado Denver
   *> \author NAG Ltd.
   *
   *> \ingroup doubleGEcomputational
   *
   *  =====================================================================
         DOUBLE PRECISION FUNCTION DLA_GERCOND( TRANS, N, A, LDA, AF,
        $                                       LDAF, IPIV, CMODE, C,
        $                                       INFO, WORK, IWORK )
   *
   *  -- LAPACK computational routine --
   *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
   *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
 *  *
       IMPLICIT NONE  
 *     ..  
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       CHARACTER          TRANS        CHARACTER          TRANS
       INTEGER            N, LDA, LDAF, INFO, CMODE        INTEGER            N, LDA, LDAF, INFO, CMODE
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      $                   C( * )       $                   C( * )
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *     DLA_GERCOND estimates the Skeel condition number of op(A) * op2(C)  
 *     where op2 is determined by CMODE as follows  
 *     CMODE =  1    op2(C) = C  
 *     CMODE =  0    op2(C) = I  
 *     CMODE = -1    op2(C) = inv(C)  
 *     The Skeel condition number cond(A) = norminf( |inv(A)||A| )  
 *     is computed by computing scaling factors R such that  
 *     diag(R)*A*op2(C) is row equilibrated and computing the standard  
 *     infinity-norm condition number.  
 *  
 *  Arguments  
 *  ==========  
 *  
 *     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 = Transpose)  
 *  
 *     N       (input) INTEGER  
 *     The number of linear equations, i.e., the order of the  
 *     matrix A.  N >= 0.  
 *  
 *     A       (input) DOUBLE PRECISION array, dimension (LDA,N)  
 *     On entry, the N-by-N matrix A.  
 *  
 *     LDA     (input) INTEGER  
 *     The leading dimension of the array A.  LDA >= max(1,N).  
 *  
 *     AF      (input) DOUBLE PRECISION array, dimension (LDAF,N)  
 *     The factors L and U from the factorization  
 *     A = P*L*U as computed by DGETRF.  
 *  
 *     LDAF    (input) INTEGER  
 *     The leading dimension of the array AF.  LDAF >= max(1,N).  
 *  
 *     IPIV    (input) INTEGER array, dimension (N)  
 *     The pivot indices from the factorization A = P*L*U  
 *     as computed by DGETRF; row i of the matrix was interchanged  
 *     with row IPIV(i).  
 *  
 *     CMODE   (input) INTEGER  
 *     Determines op2(C) in the formula op(A) * op2(C) as follows:  
 *     CMODE =  1    op2(C) = C  
 *     CMODE =  0    op2(C) = I  
 *     CMODE = -1    op2(C) = inv(C)  
 *  
 *     C       (input) DOUBLE PRECISION array, dimension (N)  
 *     The vector C in the formula op(A) * op2(C).  
 *  
 *     INFO    (output) INTEGER  
 *       = 0:  Successful exit.  
 *     i > 0:  The ith argument is invalid.  
 *  
 *     WORK    (input) DOUBLE PRECISION array, dimension (3*N).  
 *     Workspace.  
 *  
 *     IWORK   (input) INTEGER array, dimension (N).  
 *     Workspace.  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Local Scalars ..  *     .. Local Scalars ..
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             END IF              END IF
          ELSE           ELSE
 *  *
 *           Multiply by inv(C').  *           Multiply by inv(C**T).
 *  *
             IF ( CMODE .EQ. 1 ) THEN              IF ( CMODE .EQ. 1 ) THEN
                DO I = 1, N                 DO I = 1, N
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 *  *
       RETURN        RETURN
 *  *
   *     End of DLA_GERCOND
   *
       END        END
Removed from v.1.4  
changed lines
  Added in v.1.17

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