101 SUBROUTINE zgetrf ( M, N, A, LDA, IPIV, INFO)
109 INTEGER INFO, LDA, M, N
113 COMPLEX*16 A( lda, * )
120 parameter( one = ( 1.0d+0, 0.0d+0 ) )
123 INTEGER I, IINFO, J, JB, NB
142 ELSE IF( n.LT.0 )
THEN
144 ELSE IF( lda.LT.max( 1, m ) )
THEN
148 CALL
xerbla(
'ZGETRF', -info )
154 IF( m.EQ.0 .OR. n.EQ.0 )
159 nb = ilaenv( 1,
'ZGETRF',
' ', m, n, -1, -1 )
160 IF( nb.LE.1 .OR. nb.GE.min( m, n ) )
THEN
164 CALL
zgetf2( m, n, a, lda, ipiv, info )
169 DO 20 j = 1, min( m, n ), nb
170 jb = min( min( m, n )-j+1, nb )
174 CALL
zgemm(
'No transpose',
'No transpose',
175 $ m-j+1, jb, j-1, -one,
176 $ a( j, 1 ), lda, a( 1, j ), lda, one,
183 CALL
zgetf2( m-j+1, jb, a( j, j ), lda, ipiv( j ), iinfo )
187 IF( info.EQ.0 .AND. iinfo.GT.0 )
188 $ info = iinfo + j - 1
189 DO 10 i = j, min( m, j+jb-1 )
190 ipiv( i ) = j - 1 + ipiv( i )
195 CALL
zlaswp( j-1, a, lda, j, j+jb-1, ipiv, 1 )
197 IF ( j+jb.LE.n )
THEN
201 CALL
zlaswp( n-j-jb+1, a( 1, j+jb ), lda, j, j+jb-1,
204 CALL
zgemm(
'No transpose',
'No transpose',
205 $ jb, n-j-jb+1, j-1, -one,
206 $ a( j, 1 ), lda, a( 1, j+jb ), lda, one,
207 $ a( j, j+jb ), lda )
211 CALL
ztrsm(
'Left',
'Lower',
'No transpose',
'Unit',
212 $ jb, n-j-jb+1, one, a( j, j ), lda,
213 $ a( j, j+jb ), lda )
subroutine ztrsm(SIDE, UPLO, TRANSA, DIAG, M, N, ALPHA, A, LDA, B, LDB)
ZTRSM
subroutine zgemm(TRANSA, TRANSB, M, N, K, ALPHA, A, LDA, B, LDB, BETA, C, LDC)
ZGEMM
subroutine xerbla(SRNAME, INFO)
XERBLA
subroutine zgetf2(M, N, A, LDA, IPIV, INFO)
ZGETF2 computes the LU factorization of a general m-by-n matrix using partial pivoting with row inter...
subroutine zlaswp(N, A, LDA, K1, K2, IPIV, INCX)
ZLASWP performs a series of row interchanges on a general rectangular matrix.
subroutine zgetrf(M, N, A, LDA, IPIV, INFO)
ZGETRF VARIANT: Crout Level 3 BLAS version of the algorithm.