zpocon.f man page

zpocon.f

Synopsis

Functions/Subroutines

subroutine zpocon (UPLO, N, A, LDA, ANORM, RCOND, WORK, RWORK, INFO)
ZPOCON

Function/Subroutine Documentation

subroutine zpocon (character UPLO, integer N, complex*16, dimension( lda, * ) A, integer LDA, double precision ANORM, double precision RCOND, complex*16, dimension( * ) WORK, double precision, dimension( * ) RWORK, integer INFO)

ZPOCON  

Purpose:

 ZPOCON estimates the reciprocal of the condition number (in the
 1-norm) of a complex Hermitian positive definite matrix using the
 Cholesky factorization A = U**H*U or A = L*L**H computed by ZPOTRF.

 An estimate is obtained for norm(inv(A)), and the reciprocal of the
 condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).
Parameters:

UPLO

          UPLO is CHARACTER*1
          = 'U':  Upper triangle of A is stored;
          = 'L':  Lower triangle of A is stored.

N

          N is INTEGER
          The order of the matrix A.  N >= 0.

A

          A is COMPLEX*16 array, dimension (LDA,N)
          The triangular factor U or L from the Cholesky factorization
          A = U**H*U or A = L*L**H, as computed by ZPOTRF.

LDA

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

ANORM

          ANORM is DOUBLE PRECISION
          The 1-norm (or infinity-norm) of the Hermitian matrix A.

RCOND

          RCOND is DOUBLE PRECISION
          The reciprocal of the condition number of the matrix A,
          computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an
          estimate of the 1-norm of inv(A) computed in this routine.

WORK

          WORK is COMPLEX*16 array, dimension (2*N)

RWORK

          RWORK is DOUBLE PRECISION array, dimension (N)

INFO

          INFO is INTEGER
          = 0:  successful exit
          < 0:  if INFO = -i, the i-th argument had an illegal value
Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

December 2016

Definition at line 123 of file zpocon.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page zpocon(3) is an alias of zpocon.f(3).

Tue Nov 14 2017 Version 3.8.0 LAPACK