ztpt01.f - Man Page

TESTING/LIN/ztpt01.f

Synopsis

Functions/Subroutines

subroutine ztpt01 (uplo, diag, n, ap, ainvp, rcond, rwork, resid)
ZTPT01

Function/Subroutine Documentation

subroutine ztpt01 (character uplo, character diag, integer n, complex*16, dimension( * ) ap, complex*16, dimension( * ) ainvp, double precision rcond, double precision, dimension( * ) rwork, double precision resid)

ZTPT01

Purpose:

 ZTPT01 computes the residual for a triangular matrix A times its
 inverse when A is stored in packed format:
    RESID = norm(A*AINV - I) / ( N * norm(A) * norm(AINV) * EPS ),
 where EPS is the machine epsilon.
Parameters

UPLO

          UPLO is CHARACTER*1
          Specifies whether the matrix A is upper or lower triangular.
          = 'U':  Upper triangular
          = 'L':  Lower triangular

DIAG

          DIAG is CHARACTER*1
          Specifies whether or not the matrix A is unit triangular.
          = 'N':  Non-unit triangular
          = 'U':  Unit triangular

N

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

AP

          AP is COMPLEX*16 array, dimension (N*(N+1)/2)
          The original upper or lower triangular matrix A, packed
          columnwise in a linear array.  The j-th column of A is stored
          in the array AP as follows:
          if UPLO = 'U', AP((j-1)*j/2 + i) = A(i,j) for 1<=i<=j;
          if UPLO = 'L',
             AP((j-1)*(n-j) + j*(j+1)/2 + i-j) = A(i,j) for j<=i<=n.

AINVP

          AINVP is COMPLEX*16 array, dimension (N*(N+1)/2)
          On entry, the (triangular) inverse of the matrix A, packed
          columnwise in a linear array as in AP.
          On exit, the contents of AINVP are destroyed.

RCOND

          RCOND is DOUBLE PRECISION
          The reciprocal condition number of A, computed as
          1/(norm(A) * norm(AINV)).

RWORK

          RWORK is DOUBLE PRECISION array, dimension (N)

RESID

          RESID is DOUBLE PRECISION
          norm(A*AINV - I) / ( N * norm(A) * norm(AINV) * EPS )
Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 108 of file ztpt01.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page ztpt01(3) is an alias of ztpt01.f(3).

Tue Nov 28 2023 12:08:43 Version 3.12.0 LAPACK