DLA_GERCONDLAPACK routine (version 3.2)DLA_GERCOND(1)NAMEDLA_GERCOND - DLA_GERCOND 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 = -1op2(C) = inv(C) The Skeel condiā
tion 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_GERCOND ( TRANS, N, A, LDA, AF, LDAF,
IPIV, CMODE, C, INFO, WORK, IWORK )
IMPLICIT NONE
CHARACTER TRANS
INTEGER N, LDA, LDAF, INFO, CMODE
INTEGER IPIV( * ), IWORK( * )
DOUBLE PRECISION A( LDA, * ), AF( LDAF, * ), WORK( * ), C( *
)
PURPOSEDLA_GERCOND estimates 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 = -1op2(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, and
IWORK INTEGER workspace of size N.
LAPACK routine (version 3.2) November 2008 DLA_GERCOND(1)