cpocon.f - Man Page

SRC/cpocon.f

Synopsis

Functions/Subroutines

subroutine cpocon (uplo, n, a, lda, anorm, rcond, work, rwork, info)
CPOCON

Function/Subroutine Documentation

subroutine cpocon (character uplo, integer n, complex, dimension( lda, * ) a, integer lda, real anorm, real rcond, complex, dimension( * ) work, real, dimension( * ) rwork, integer info)

CPOCON  

Purpose:

 CPOCON 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 CPOTRF.

 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 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 CPOTRF.

LDA

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

ANORM

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

RCOND

          RCOND is REAL
          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 array, dimension (2*N)

RWORK

          RWORK is REAL 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.

Definition at line 119 of file cpocon.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

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

Tue Nov 28 2023 12:08:41 Version 3.12.0 LAPACK