TESTING/LIN/dspt01.f(3) Library Functions Manual TESTING/LIN/dspt01.f(3) NAME TESTING/LIN/dspt01.f SYNOPSIS Functions/Subroutines subroutine dspt01 (uplo, n, a, afac, ipiv, c, ldc, rwork, resid) DSPT01 Function/Subroutine Documentation subroutine dspt01 (character uplo, integer n, double precision, dimension( * ) a, double precision, dimension( * ) afac, integer, dimension( * ) ipiv, double precision, dimension( ldc, * ) c, integer ldc, double precision, dimension( * ) rwork, double precision resid) DSPT01 Purpose: DSPT01 reconstructs a symmetric indefinite packed matrix A from its block L*D*L' or U*D*U' factorization 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 symmetric 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 DOUBLE PRECISION array, dimension (N*(N+1)/2) The original symmetric matrix A, stored as a packed triangular matrix. AFAC AFAC is DOUBLE PRECISION array, dimension (N*(N+1)/2) The factored form of the matrix A, stored as a packed triangular matrix. AFAC contains the block diagonal matrix D and the multipliers used to obtain the factor L or U from the block L*D*L' or U*D*U' factorization as computed by DSPTRF. IPIV IPIV is INTEGER array, dimension (N) The pivot indices from DSPTRF. C C is DOUBLE PRECISION array, dimension (LDC,N) LDC LDC is INTEGER The leading dimension of the array C. LDC >= max(1,N). RWORK RWORK is DOUBLE PRECISION array, dimension (N) RESID RESID is DOUBLE PRECISION 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 109 of file dspt01.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/dspt01.f(3)