148 SUBROUTINE slasd0( N, SQRE, D, E, U, LDU, VT, LDVT, SMLSIZ, IWORK,
156 INTEGER INFO, LDU, LDVT, N, SMLSIZ, SQRE
160 REAL D( * ), E( * ), U( LDU, * ), VT( LDVT, * ),
167 INTEGER I, I1, IC, IDXQ, IDXQC, IM1, INODE, ITEMP, IWK,
168 $ j, lf, ll, lvl, m, ncc, nd, ndb1, ndiml, ndimr,
169 $ nl, nlf, nlp1, nlvl, nr, nrf, nrp1, sqrei
183 ELSE IF( ( sqre.LT.0 ) .OR. ( sqre.GT.1 ) )
THEN
191 ELSE IF( ldvt.LT.m )
THEN
193 ELSE IF( smlsiz.LT.3 )
THEN
197 CALL xerbla(
'SLASD0', -info )
203 IF( n.LE.smlsiz )
THEN
204 CALL slasdq(
'U', sqre, n, m, n, 0, d, e, vt, ldvt, u, ldu, u,
216 CALL slasdt( n, nlvl, nd, iwork( inode ), iwork( ndiml ),
217 $ iwork( ndimr ), smlsiz )
233 ic = iwork( inode+i1 )
234 nl = iwork( ndiml+i1 )
236 nr = iwork( ndimr+i1 )
241 CALL slasdq(
'U', sqrei, nl, nlp1, nl, ncc, d( nlf ), e( nlf ),
242 $ vt( nlf, nlf ), ldvt, u( nlf, nlf ), ldu,
243 $ u( nlf, nlf ), ldu, work, info )
247 itemp = idxq + nlf - 2
257 CALL slasdq(
'U', sqrei, nr, nrp1, nr, ncc, d( nrf ), e( nrf ),
258 $ vt( nrf, nrf ), ldvt, u( nrf, nrf ), ldu,
259 $ u( nrf, nrf ), ldu, work, info )
265 iwork( itemp+j-1 ) = j
271 DO 50 lvl = nlvl, 1, -1
285 ic = iwork( inode+im1 )
286 nl = iwork( ndiml+im1 )
287 nr = iwork( ndimr+im1 )
289 IF( ( sqre.EQ.0 ) .AND. ( i.EQ.ll ) )
THEN
294 idxqc = idxq + nlf - 1
297 CALL slasd1( nl, nr, sqrei, d( nlf ), alpha, beta,
298 $ u( nlf, nlf ), ldu, vt( nlf, nlf ), ldvt,
299 $ iwork( idxqc ), iwork( iwk ), work, info )
subroutine slasd0(N, SQRE, D, E, U, LDU, VT, LDVT, SMLSIZ, IWORK, WORK, INFO)
SLASD0 computes the singular values of a real upper bidiagonal n-by-m matrix B with diagonal d and of...
subroutine slasd1(NL, NR, SQRE, D, ALPHA, BETA, U, LDU, VT, LDVT, IDXQ, IWORK, WORK, INFO)
SLASD1 computes the SVD of an upper bidiagonal matrix B of the specified size. Used by sbdsdc.
subroutine slasdq(UPLO, SQRE, N, NCVT, NRU, NCC, D, E, VT, LDVT, U, LDU, C, LDC, WORK, INFO)
SLASDQ computes the SVD of a real bidiagonal matrix with diagonal d and off-diagonal e....
subroutine slasdt(N, LVL, ND, INODE, NDIML, NDIMR, MSUB)
SLASDT creates a tree of subproblems for bidiagonal divide and conquer. Used by sbdsdc.
subroutine xerbla(SRNAME, INFO)
XERBLA