122 SUBROUTINE dppt02( UPLO, N, NRHS, A, X, LDX, B, LDB, RWORK,
132 INTEGER ldb, ldx, n, nrhs
133 DOUBLE PRECISION resid
136 DOUBLE PRECISION a( * ),
b( ldb, * ), rwork( * ), x( ldx, * )
142 DOUBLE PRECISION zero, one
143 parameter( zero = 0.0d+0, one = 1.0d+0 )
147 DOUBLE PRECISION anorm, bnorm, eps, xnorm
163 IF( n.LE.0 .OR. nrhs.LE.0 )
THEN
171 anorm =
dlansp(
'1', uplo, n, a, rwork )
172 IF( anorm.LE.zero )
THEN
180 CALL
dspmv( uplo, n, -one, a, x( 1,
j ), 1, one,
b( 1,
j ), 1 )
188 bnorm =
dasum( n,
b( 1,
j ), 1 )
189 xnorm =
dasum( n, x( 1,
j ), 1 )
190 IF( xnorm.LE.zero )
THEN
193 resid = max( resid, ( ( bnorm / anorm ) / xnorm ) / eps )
subroutine dspmv(UPLO, N, ALPHA, AP, X, INCX, BETA, Y, INCY)
DSPMV
double precision function dlansp(NORM, UPLO, N, AP, WORK)
DLANSP returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a symmetric matrix supplied in packed form.
subroutine dppt02(UPLO, N, NRHS, A, X, LDX, B, LDB, RWORK, RESID)
DPPT02
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real b(3) integer i
double precision function dlamch(CMACH)
DLAMCH
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real j
double precision function dasum(N, DX, INCX)
DASUM