dla_porcond (l) - Linux Man Pages

dla_porcond: DLA_PORCOND Estimate the Skeel condition number of op(A) * op2(C) where op2 is determined by CMODE as follows CMODE = 1 op2(C) = C CMODE = 0 op2(C) = I CMODE = -1 op2(C) = inv(C) The Skeel condition number cond(A) = norminf( |inv(A)||A| ) is computed by computing scaling factors R such that diag(R)*A*op2(C) is row equilibrated and computing the standard infinity-norm condition number

NAME

DLA_PORCOND - DLA_PORCOND Estimate the Skeel condition number of op(A) * op2(C) where op2 is determined by CMODE as follows CMODE = 1 op2(C) = C CMODE = 0 op2(C) = I CMODE = -1 op2(C) = inv(C) The Skeel condition number cond(A) = norminf( |inv(A)||A| ) is computed by computing scaling factors R such that diag(R)*A*op2(C) is row equilibrated and computing the standard infinity-norm condition number

SYNOPSIS

DOUBLE PRECISION
FUNCTION DLA_PORCOND( UPLO, N, A, LDA, AF, LDAF, CMODE, C, INFO, WORK, IWORK )

    
IMPLICIT NONE

    
CHARACTER UPLO

    
INTEGER N, LDA, LDAF, INFO, CMODE

    
DOUBLE PRECISION A( LDA, * ), AF( LDAF, * ), WORK( * ), C( * )

    
INTEGER IWORK( * )

PURPOSE


DLA_PORCOND Estimates the Skeel condition number of  op(A) op2(C)
where op2 is determined by CMODE as follows
CMODE     op2(C) C
CMODE     op2(C) I
CMODE -1    op2(C) inv(C)
The Skeel condition number  cond(A) norminf( |inv(A)||A| )
is computed by computing scaling factors R such that
diag(R)*A*op2(C) is row equilibrated and computing the standard
infinity-norm condition number.

ARGUMENTS

WORK double precision workspace of size 3*N.
IWORK integer workspace of size N.