DOUBLE PRECISION function zla_porpvgrw (UPLO, NCOLS, A, LDA, AF, LDAF, WORK)
DOUBLE PRECISION function zla_porpvgrw (character*1UPLO, integerNCOLS, complex*16, dimension( lda, * )A, integerLDA, complex*16, dimension( ldaf, * )AF, integerLDAF, double precision, dimension( * )WORK)ZLA_PORPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a symmetric or Hermitian positive-definite matrix. Purpose:
ZLA_PORPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U). The "max absolute element" norm is used. If this is much less than 1, the stability of the LU factorization of the (equilibrated) matrix A could be poor. This also means that the solution X, estimated condition numbers, and error bounds could be unreliable.
UPLO is CHARACTER*1 = 'U': Upper triangle of A is stored; = 'L': Lower triangle of A is stored.NCOLS
NCOLS is INTEGER The number of columns of the matrix A. NCOLS >= 0.A
A is COMPLEX*16 array, dimension (LDA,N) On entry, the N-by-N matrix A.LDA
LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N).AF
AF is COMPLEX*16 array, dimension (LDAF,N) The triangular factor U or L from the Cholesky factorization A = U**T*U or A = L*L**T, as computed by ZPOTRF.LDAF
LDAF is INTEGER The leading dimension of the array AF. LDAF >= max(1,N).WORK
WORK is COMPLEX*16 array, dimension (2*N)
Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd.Date:
September 2012Definition at line 107 of file zla_porpvgrw.f.