171 SUBROUTINE dpbt05( UPLO, N, KD, NRHS, AB, LDAB, B, LDB, X, LDX,
172 $ xact, ldxact, ferr, berr, reslts )
181 INTEGER kd, ldab, ldb, ldx, ldxact, n, nrhs
184 DOUBLE PRECISION ab( ldab, * ),
b( ldb, * ), berr( * ),
185 $ ferr( * ), reslts( * ), x( ldx, * ),
192 DOUBLE PRECISION zero, one
193 parameter( zero = 0.0d+0, one = 1.0d+0 )
197 INTEGER i, imax,
j, k, nz
198 DOUBLE PRECISION axbi, diff, eps, errbnd, ovfl, tmp, unfl, xnorm
207 INTRINSIC abs, max, min
213 IF( n.LE.0 .OR. nrhs.LE.0 )
THEN
220 unfl =
dlamch(
'Safe minimum' )
222 upper =
lsame( uplo,
'U' )
223 nz = 2*max( kd, n-1 ) + 1
231 imax =
idamax( n, x( 1,
j ), 1 )
232 xnorm = max( abs( x( imax,
j ) ), unfl )
235 diff = max( diff, abs( x( i,
j )-xact( i,
j ) ) )
238 IF( xnorm.GT.one )
THEN
240 ELSE IF( diff.LE.ovfl*xnorm )
THEN
248 IF( diff / xnorm.LE.ferr(
j ) )
THEN
249 errbnd = max( errbnd, ( diff / xnorm ) / ferr(
j ) )
261 tmp = abs(
b( i, k ) )
263 DO 40
j = max( i-kd, 1 ), i
264 tmp = tmp + abs( ab( kd+1-i+
j, i ) )*abs( x(
j, k ) )
266 DO 50
j = i + 1, min( i+kd, n )
267 tmp = tmp + abs( ab( kd+1+i-
j,
j ) )*abs( x(
j, k ) )
270 DO 60
j = max( i-kd, 1 ), i - 1
271 tmp = tmp + abs( ab( 1+i-
j,
j ) )*abs( x(
j, k ) )
273 DO 70
j = i, min( i+kd, n )
274 tmp = tmp + abs( ab( 1+
j-i, i ) )*abs( x(
j, k ) )
280 axbi = min( axbi, tmp )
283 tmp = berr( k ) / ( nz*eps+nz*unfl / max( axbi, nz*unfl ) )
287 reslts( 2 ) = max( reslts( 2 ), tmp )
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real b(3) integer i
logical function lsame(CA, CB)
LSAME
subroutine dpbt05(UPLO, N, KD, NRHS, AB, LDAB, B, LDB, X, LDX, XACT, LDXACT, FERR, BERR, RESLTS)
DPBT05
double precision function dlamch(CMACH)
DLAMCH
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real j
integer function idamax(N, DX, INCX)
IDAMAX