146 SUBROUTINE zgbtf2( M, N, KL, KU, AB, LDAB, IPIV, INFO )
154 INTEGER info, kl, ku, ldab, m, n
158 COMPLEX*16 ab( ldab, * )
165 parameter( one = ( 1.0d+0, 0.0d+0 ),
166 $ zero = ( 0.0d+0, 0.0d+0 ) )
169 INTEGER i,
j, jp, ju, km, kv
193 ELSE IF( n.LT.0 )
THEN
195 ELSE IF( kl.LT.0 )
THEN
197 ELSE IF( ku.LT.0 )
THEN
199 ELSE IF( ldab.LT.kl+kv+1 )
THEN
203 CALL
xerbla(
'ZGBTF2', -info )
209 IF( m.EQ.0 .OR. n.EQ.0 )
216 DO 20
j = ku + 2, min( kv, n )
217 DO 10 i = kv -
j + 2, kl
227 DO 40
j = 1, min( m, n )
241 jp =
izamax( km+1, ab( kv+1,
j ), 1 )
242 ipiv(
j ) = jp +
j - 1
243 IF( ab( kv+jp,
j ).NE.zero )
THEN
244 ju = max( ju, min(
j+ku+jp-1, n ) )
249 $ CALL
zswap( ju-
j+1, ab( kv+jp,
j ), ldab-1,
250 $ ab( kv+1,
j ), ldab-1 )
255 CALL
zscal( km, one / ab( kv+1,
j ), ab( kv+2,
j ), 1 )
260 $ CALL
zgeru( km, ju-
j, -one, ab( kv+2,
j ), 1,
261 $ ab( kv,
j+1 ), ldab-1, ab( kv+1,
j+1 ),
subroutine zswap(N, ZX, INCX, ZY, INCY)
ZSWAP
integer function izamax(N, ZX, INCX)
IZAMAX
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine zgbtf2(M, N, KL, KU, AB, LDAB, IPIV, INFO)
ZGBTF2 computes the LU factorization of a general band matrix using the unblocked version of the algo...
set ue cd $ADTTMP cat<< EOF > tmp f Program LinearEquations Implicit none Real j
subroutine zscal(N, ZA, ZX, INCX)
ZSCAL
subroutine zgeru(M, N, ALPHA, X, INCX, Y, INCY, A, LDA)
ZGERU