TESTING/LIN/ctrt01.f(3) | Library Functions Manual | TESTING/LIN/ctrt01.f(3) |
NAME
TESTING/LIN/ctrt01.f
SYNOPSIS
Functions/Subroutines
subroutine ctrt01 (uplo, diag, n, a, lda, ainv, ldainv,
rcond, rwork, resid)
CTRT01
Function/Subroutine Documentation
subroutine ctrt01 (character uplo, character diag, integer n, complex, dimension( lda, * ) a, integer lda, complex, dimension( ldainv, * ) ainv, integer ldainv, real rcond, real, dimension( * ) rwork, real resid)
CTRT01
Purpose:
CTRT01 computes the residual for a triangular matrix A times its inverse: 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.
A
A is COMPLEX array, dimension (LDA,N) The triangular matrix A. If UPLO = 'U', the leading n by n upper triangular part of the array A contains the upper triangular matrix, and the strictly lower triangular part of A is not referenced. If UPLO = 'L', the leading n by n lower triangular part of the array A contains the lower triangular matrix, and the strictly upper triangular part of A is not referenced. If DIAG = 'U', the diagonal elements of A are also not referenced and are assumed to be 1.
LDA
LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N).
AINV
AINV is COMPLEX array, dimension (LDAINV,N) On entry, the (triangular) inverse of the matrix A, in the same storage format as A. On exit, the contents of AINV are destroyed.
LDAINV
LDAINV is INTEGER The leading dimension of the array AINV. LDAINV >= max(1,N).
RCOND
RCOND is REAL The reciprocal condition number of A, computed as 1/(norm(A) * norm(AINV)).
RWORK
RWORK is REAL array, dimension (N)
RESID
RESID is REAL 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 123 of file ctrt01.f.
Author
Generated automatically by Doxygen for LAPACK from the source code.
Version 3.12.0 | LAPACK |