LAPACK  3.5.0
LAPACK: Linear Algebra PACKage
 All Files Functions Typedefs Macros
zpot01.f File Reference

Go to the source code of this file.

Functions/Subroutines

subroutine zpot01 (UPLO, N, A, LDA, AFAC, LDAFAC, RWORK, RESID)
 ZPOT01 More...
 

Function/Subroutine Documentation

subroutine zpot01 ( character  UPLO,
integer  N,
complex*16, dimension( lda, * )  A,
integer  LDA,
complex*16, dimension( ldafac, * )  AFAC,
integer  LDAFAC,
double precision, dimension( * )  RWORK,
double precision  RESID 
)

ZPOT01

Purpose:
 ZPOT01 reconstructs a Hermitian positive definite matrix  A  from
 its L*L' or U'*U factorization and computes the residual
    norm( L*L' - A ) / ( N * norm(A) * EPS ) or
    norm( U'*U - A ) / ( N * norm(A) * EPS ),
 where EPS is the machine epsilon, L' is the conjugate transpose of L,
 and U' is the conjugate transpose of U.
Parameters
[in]UPLO
          UPLO is CHARACTER*1
          Specifies whether the upper or lower triangular part of the
          Hermitian matrix A is stored:
          = 'U':  Upper triangular
          = 'L':  Lower triangular
[in]N
          N is INTEGER
          The number of rows and columns of the matrix A.  N >= 0.
[in]A
          A is COMPLEX*16 array, dimension (LDA,N)
          The original Hermitian matrix A.
[in]LDA
          LDA is INTEGER
          The leading dimension of the array A.  LDA >= max(1,N)
[in,out]AFAC
          AFAC is COMPLEX*16 array, dimension (LDAFAC,N)
          On entry, the factor L or U from the L*L' or U'*U
          factorization of A.
          Overwritten with the reconstructed matrix, and then with the
          difference L*L' - A (or U'*U - A).
[in]LDAFAC
          LDAFAC is INTEGER
          The leading dimension of the array AFAC.  LDAFAC >= max(1,N).
[out]RWORK
          RWORK is DOUBLE PRECISION array, dimension (N)
[out]RESID
          RESID is DOUBLE PRECISION
          If UPLO = 'L', norm(L*L' - A) / ( N * norm(A) * EPS )
          If UPLO = 'U', norm(U'*U - A) / ( N * norm(A) * EPS )
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date
November 2011

Definition at line 107 of file zpot01.f.

Here is the call graph for this function:

Here is the caller graph for this function: