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version 1.8, 2011/07/22 07:38:12 version 1.9, 2011/11/21 20:43:05
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   *> \brief \b DTBCON
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *> \htmlonly
   *> Download DTBCON + dependencies 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dtbcon.f"> 
   *> [TGZ]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dtbcon.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dtbcon.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DTBCON( NORM, UPLO, DIAG, N, KD, AB, LDAB, RCOND, WORK,
   *                          IWORK, INFO )
   * 
   *       .. Scalar Arguments ..
   *       CHARACTER          DIAG, NORM, UPLO
   *       INTEGER            INFO, KD, LDAB, N
   *       DOUBLE PRECISION   RCOND
   *       ..
   *       .. Array Arguments ..
   *       INTEGER            IWORK( * )
   *       DOUBLE PRECISION   AB( LDAB, * ), WORK( * )
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> DTBCON estimates the reciprocal of the condition number of a
   *> triangular band matrix A, in either the 1-norm or the infinity-norm.
   *>
   *> The norm of A is computed and an estimate is obtained for
   *> norm(inv(A)), then the reciprocal of the condition number is
   *> computed as
   *>    RCOND = 1 / ( norm(A) * norm(inv(A)) ).
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] NORM
   *> \verbatim
   *>          NORM is CHARACTER*1
   *>          Specifies whether the 1-norm condition number or the
   *>          infinity-norm condition number is required:
   *>          = '1' or 'O':  1-norm;
   *>          = 'I':         Infinity-norm.
   *> \endverbatim
   *>
   *> \param[in] UPLO
   *> \verbatim
   *>          UPLO is CHARACTER*1
   *>          = 'U':  A is upper triangular;
   *>          = 'L':  A is lower triangular.
   *> \endverbatim
   *>
   *> \param[in] DIAG
   *> \verbatim
   *>          DIAG is CHARACTER*1
   *>          = 'N':  A is non-unit triangular;
   *>          = 'U':  A is unit triangular.
   *> \endverbatim
   *>
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>          The order of the matrix A.  N >= 0.
   *> \endverbatim
   *>
   *> \param[in] KD
   *> \verbatim
   *>          KD is INTEGER
   *>          The number of superdiagonals or subdiagonals of the
   *>          triangular band matrix A.  KD >= 0.
   *> \endverbatim
   *>
   *> \param[in] AB
   *> \verbatim
   *>          AB is DOUBLE PRECISION array, dimension (LDAB,N)
   *>          The upper or lower triangular band matrix A, stored in the
   *>          first kd+1 rows of the array. 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).
   *>          If DIAG = 'U', the diagonal elements of A are not referenced
   *>          and are assumed to be 1.
   *> \endverbatim
   *>
   *> \param[in] LDAB
   *> \verbatim
   *>          LDAB is INTEGER
   *>          The leading dimension of the array AB.  LDAB >= KD+1.
   *> \endverbatim
   *>
   *> \param[out] RCOND
   *> \verbatim
   *>          RCOND is DOUBLE PRECISION
   *>          The reciprocal of the condition number of the matrix A,
   *>          computed as RCOND = 1/(norm(A) * norm(inv(A))).
   *> \endverbatim
   *>
   *> \param[out] WORK
   *> \verbatim
   *>          WORK is DOUBLE PRECISION array, dimension (3*N)
   *> \endverbatim
   *>
   *> \param[out] IWORK
   *> \verbatim
   *>          IWORK is INTEGER array, dimension (N)
   *> \endverbatim
   *>
   *> \param[out] INFO
   *> \verbatim
   *>          INFO is INTEGER
   *>          = 0:  successful exit
   *>          < 0:  if INFO = -i, the i-th argument had an illegal value
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup doubleOTHERcomputational
   *
   *  =====================================================================
       SUBROUTINE DTBCON( NORM, UPLO, DIAG, N, KD, AB, LDAB, RCOND, WORK,        SUBROUTINE DTBCON( NORM, UPLO, DIAG, N, KD, AB, LDAB, RCOND, WORK,
      $                   IWORK, INFO )       $                   IWORK, INFO )
 *  *
 *  -- LAPACK routine (version 3.2) --  *  -- LAPACK computational routine (version 3.4.0) --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
 *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
 *     November 2006  *     November 2011
 *  
 *     Modified to call DLACN2 in place of DLACON, 5 Feb 03, SJH.  
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       CHARACTER          DIAG, NORM, UPLO        CHARACTER          DIAG, NORM, UPLO
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       DOUBLE PRECISION   AB( LDAB, * ), WORK( * )        DOUBLE PRECISION   AB( LDAB, * ), WORK( * )
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  DTBCON estimates the reciprocal of the condition number of a  
 *  triangular band matrix A, in either the 1-norm or the infinity-norm.  
 *  
 *  The norm of A is computed and an estimate is obtained for  
 *  norm(inv(A)), then the reciprocal of the condition number is  
 *  computed as  
 *     RCOND = 1 / ( norm(A) * norm(inv(A)) ).  
 *  
 *  Arguments  
 *  =========  
 *  
 *  NORM    (input) CHARACTER*1  
 *          Specifies whether the 1-norm condition number or the  
 *          infinity-norm condition number is required:  
 *          = '1' or 'O':  1-norm;  
 *          = 'I':         Infinity-norm.  
 *  
 *  UPLO    (input) CHARACTER*1  
 *          = 'U':  A is upper triangular;  
 *          = 'L':  A is lower triangular.  
 *  
 *  DIAG    (input) CHARACTER*1  
 *          = 'N':  A is non-unit triangular;  
 *          = 'U':  A is unit triangular.  
 *  
 *  N       (input) INTEGER  
 *          The order of the matrix A.  N >= 0.  
 *  
 *  KD      (input) INTEGER  
 *          The number of superdiagonals or subdiagonals of the  
 *          triangular band matrix A.  KD >= 0.  
 *  
 *  AB      (input) DOUBLE PRECISION array, dimension (LDAB,N)  
 *          The upper or lower triangular band matrix A, stored in the  
 *          first kd+1 rows of the array. 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).  
 *          If DIAG = 'U', the diagonal elements of A are not referenced  
 *          and are assumed to be 1.  
 *  
 *  LDAB    (input) INTEGER  
 *          The leading dimension of the array AB.  LDAB >= KD+1.  
 *  
 *  RCOND   (output) DOUBLE PRECISION  
 *          The reciprocal of the condition number of the matrix A,  
 *          computed as RCOND = 1/(norm(A) * norm(inv(A))).  
 *  
 *  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  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.8  
changed lines
  Added in v.1.9

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