136 SUBROUTINE spbt02( UPLO, N, KD, NRHS, A, LDA, X, LDX, B, LDB,
146 INTEGER kd, lda, ldb, ldx, n, nrhs
150 REAL a( lda, * ),
b( ldb, * ), rwork( * ),
158 parameter( zero = 0.0e+0, one = 1.0e+0 )
162 REAL anorm, bnorm, eps, xnorm
178 IF( n.LE.0 .OR. nrhs.LE.0 )
THEN
186 anorm =
slansb(
'1', uplo, n, kd, a, lda, rwork )
187 IF( anorm.LE.zero )
THEN
195 CALL
ssbmv( uplo, n, kd, -one, a, lda, x( 1,
j ), 1, one,
204 bnorm =
sasum( n,
b( 1,
j ), 1 )
205 xnorm =
sasum( n, x( 1,
j ), 1 )
206 IF( xnorm.LE.zero )
THEN
209 resid = max( resid, ( ( bnorm / anorm ) / xnorm ) / eps )
real function sasum(N, SX, INCX)
SASUM
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real b(3) integer i
real function slansb(NORM, UPLO, N, K, AB, LDAB, WORK)
SLANSB 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 band matrix.
subroutine ssbmv(UPLO, N, K, ALPHA, A, LDA, X, INCX, BETA, Y, INCY)
SSBMV
real function slamch(CMACH)
SLAMCH
subroutine spbt02(UPLO, N, KD, NRHS, A, LDA, X, LDX, B, LDB, RWORK, RESID)
SPBT02
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real j