Provided by: liblapack-doc_3.3.1-1_all bug

NAME

       LAPACK-3 - estimates the reciprocal of the condition number of a general real matrix A, in
       either the 1-norm or the infinity-norm, using the LU factorization computed by SGETRF

SYNOPSIS

       SUBROUTINE SGECON( NORM, N, A, LDA, ANORM, RCOND, WORK, IWORK, INFO )

           CHARACTER      NORM

           INTEGER        INFO, LDA, N

           REAL           ANORM, RCOND

           INTEGER        IWORK( * )

           REAL           A( LDA, * ), WORK( * )

PURPOSE

       SGECON estimates the reciprocal of the condition number of a general  real  matrix  A,  in
       either the 1-norm or the infinity-norm, using the LU factorization computed by SGETRF.
        An estimate is obtained for norm(inv(A)), and 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.

        N       (input) INTEGER
                The order of the matrix A.  N >= 0.

        A       (input) REAL array, dimension (LDA,N)
                The factors L and U from the factorization A = P*L*U
                as computed by SGETRF.

        LDA     (input) INTEGER
                The leading dimension of the array A.  LDA >= max(1,N).

        ANORM   (input) REAL
                If NORM = '1' or 'O', the 1-norm of the original matrix A.
                If NORM = 'I', the infinity-norm of the original matrix A.

        RCOND   (output) REAL
                The reciprocal of the condition number of the matrix A,
                computed as RCOND = 1/(norm(A) * norm(inv(A))).

        WORK    (workspace) REAL array, dimension (4*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

 LAPACK routine (version 3.3.1)             April 2011                            SGECON(3lapack)