LAPACK 3.11.0
LAPACK: Linear Algebra PACKage

◆ zppt03()

subroutine zppt03 ( character  UPLO,
integer  N,
complex*16, dimension( * )  A,
complex*16, dimension( * )  AINV,
complex*16, dimension( ldwork, * )  WORK,
integer  LDWORK,
double precision, dimension( * )  RWORK,
double precision  RCOND,
double precision  RESID 
)

ZPPT03

Purpose:
 ZPPT03 computes the residual for a Hermitian packed matrix times its
 inverse:
    norm( I - A*AINV ) / ( N * norm(A) * norm(AINV) * EPS ),
 where EPS is the machine epsilon.
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 (N*(N+1)/2)
          The original Hermitian matrix A, stored as a packed
          triangular matrix.
[in]AINV
          AINV is COMPLEX*16 array, dimension (N*(N+1)/2)
          The (Hermitian) inverse of the matrix A, stored as a packed
          triangular matrix.
[out]WORK
          WORK is COMPLEX*16 array, dimension (LDWORK,N)
[in]LDWORK
          LDWORK is INTEGER
          The leading dimension of the array WORK.  LDWORK >= max(1,N).
[out]RWORK
          RWORK is DOUBLE PRECISION array, dimension (N)
[out]RCOND
          RCOND is DOUBLE PRECISION
          The reciprocal of the condition number of A, computed as
          ( 1/norm(A) ) / norm(AINV).
[out]RESID
          RESID is DOUBLE PRECISION
          norm(I - A*AINV) / ( N * norm(A) * norm(AINV) * EPS )
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.