TESTING/LIN/chet01_3.f(3) Library Functions Manual TESTING/LIN/chet01_3.f(3) NAME TESTING/LIN/chet01_3.f SYNOPSIS Functions/Subroutines subroutine chet01_3 (uplo, n, a, lda, afac, ldafac, e, ipiv, c, ldc, rwork, resid) CHET01_3 Function/Subroutine Documentation subroutine chet01_3 (character uplo, integer n, complex, dimension( lda, * ) a, integer lda, complex, dimension( ldafac, * ) afac, integer ldafac, complex, dimension( * ) e, integer, dimension( * ) ipiv, complex, dimension( ldc, * ) c, integer ldc, real, dimension( * ) rwork, real resid) CHET01_3 Purpose: CHET01_3 reconstructs a Hermitian indefinite matrix A from its block L*D*L' or U*D*U' factorization computed by CHETRF_RK (or CHETRF_BK) and computes the residual norm( C - A ) / ( N * norm(A) * EPS ), where C is the reconstructed matrix and EPS is the machine epsilon. Parameters 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 N N is INTEGER The number of rows and columns of the matrix A. N >= 0. A A is COMPLEX*16 array, dimension (LDA,N) The original Hermitian matrix A. LDA LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N) AFAC AFAC is COMPLEX array, dimension (LDAFAC,N) Diagonal of the block diagonal matrix D and factors U or L as computed by CHETRF_RK and CHETRF_BK: a) ONLY diagonal elements of the Hermitian block diagonal matrix D on the diagonal of A, i.e. D(k,k) = A(k,k); (superdiagonal (or subdiagonal) elements of D should be provided on entry in array E), and b) If UPLO = 'U': factor U in the superdiagonal part of A. If UPLO = 'L': factor L in the subdiagonal part of A. LDAFAC LDAFAC is INTEGER The leading dimension of the array AFAC. LDAFAC >= max(1,N). E E is COMPLEX array, dimension (N) On entry, contains the superdiagonal (or subdiagonal) elements of the Hermitian block diagonal matrix D with 1-by-1 or 2-by-2 diagonal blocks, where If UPLO = 'U': E(i) = D(i-1,i),i=2:N, E(1) not referenced; If UPLO = 'L': E(i) = D(i+1,i),i=1:N-1, E(N) not referenced. IPIV IPIV is INTEGER array, dimension (N) The pivot indices from CHETRF_RK (or CHETRF_BK). C C is COMPLEX array, dimension (LDC,N) LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,N). RWORK RWORK is REAL array, dimension (N) RESID RESID is REAL If UPLO = 'L', norm(L*D*L' - A) / ( N * norm(A) * EPS ) If UPLO = 'U', norm(U*D*U' - A) / ( N * norm(A) * EPS ) Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 139 of file chet01_3.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/chet01_3.f(3)