226 SUBROUTINE scsdts( M, P, Q, X, XF, LDX, U1, LDU1, U2, LDU2, V1T,
227 $ LDV1T, V2T, LDV2T, THETA, IWORK, WORK, LWORK,
235 INTEGER LDX, LDU1, LDU2, LDV1T, LDV2T, LWORK, M, P, Q
239 REAL RESULT( 15 ), RWORK( * ), THETA( * )
240 REAL U1( LDU1, * ), U2( LDU2, * ), V1T( LDV1T, * ),
241 $ v2t( ldv2t, * ), work( lwork ), x( ldx, * ),
248 REAL REALONE, REALZERO
249 PARAMETER ( REALONE = 1.0e0, realzero = 0.0e0 )
251 parameter( zero = 0.0e0, one = 1.0e0 )
253 parameter( piover2 = 1.57079632679489661923132169163975144210e0 )
257 REAL , RESID, ULP, ULPINV
260 REAL SLAMCH, SLANGE, SLANSY
261 EXTERNAL SLAMCH, SLANGE,
268 INTRINSIC cos,
max,
min, real, sin
272 ulp = slamch(
'Precision' )
273 ulpinv = realone / ulp
278 CALL ssyrk(
'Upper',
'Conjugate transpose', m, m, -one, x, ldx,
282 $ slange(
'1', m, m, work, ldx, rwork ) / real( m ) )
286 r =
min( p, m-p, q, m-q )
290 CALL slacpy(
'Full', m, m, x, ldx, xf, ldx )
294 CALL sorcsd(
'Y',
'Y',
'Y',
'Y',
'N',
'D', m, p, q, xf(1,1), ldx,
295 $ xf(1,q+1), ldx, xf(p+1,1), ldx, xf(p+1,q+1), ldx,
296 $ theta, u1, ldu1, u2, ldu2, v1t, ldv1t, v2t, ldv2t,
297 $ work, lwork, iwork, info )
301 CALL slacpy(
'Full', m, m, x, ldx, xf, ldx )
303 CALL sgemm(
'No transpose',
'Conjugate transpose', p, q, q, one,
304 $ xf, ldx, v1t, ldv1t, zero, work, ldx )
306 CALL sgemm(
'Conjugate transpose',
'No transpose', p,
307 $ u1, ldu1, work, ldx, zero, xf, ldx )
310 xf(i,i) = xf(i,i) - one
313 xf(
min(p,q)-r+i,
min(p,q)-r+i) =
314 $ xf(
min(p,q)-r+i,
min(p,q)-r+i) - cos(theta(i))
317 CALL sgemm( 'no transpose
', 'conjugate transpose
', P, M-Q, M-Q,
318 $ ONE, XF(1,Q+1), LDX, V2T, LDV2T, ZERO, WORK, LDX )
320 CALL SGEMM( 'conjugate transpose
', 'no transpose
', P, M-Q, P,
321 $ ONE, U1, LDU1, WORK, LDX, ZERO, XF(1,Q+1), LDX )
323 DO I = 1, MIN(P,M-Q)-R
324 XF(P-I+1,M-I+1) = XF(P-I+1,M-I+1) + ONE
327 XF(P-(MIN(P,M-Q)-R)+1-I,M-(MIN(P,M-Q)-R)+1-I) =
328 $ XF(P-(MIN(P,M-Q)-R)+1-I,M-(MIN(P,M-Q)-R)+1-I) +
332 CALL SGEMM( 'no transpose
', 'conjugate transpose
', M-P, Q, Q, ONE,
333 $ XF(P+1,1), LDX, V1T, LDV1T, ZERO, WORK, LDX )
335 CALL SGEMM( 'conjugate transpose
', 'no transpose
', M-P, Q, M-P,
336 $ ONE, U2, LDU2, WORK, LDX, ZERO, XF(P+1,1), LDX )
338 DO I = 1, MIN(M-P,Q)-R
339 XF(M-I+1,Q-I+1) = XF(M-I+1,Q-I+1) - ONE
342 XF(M-(MIN(M-P,Q)-R)+1-I,Q-(MIN(M-P,Q)-R)+1-I) =
343 $ XF(M-(MIN(M-P,Q)-R)+1-I,Q-(MIN(M-P,Q)-R)+1-I) -
347 CALL SGEMM( 'no transpose
', 'conjugate transpose
', M-P, M-Q, M-Q,
348 $ ONE, XF(P+1,Q+1), LDX, V2T, LDV2T, ZERO, WORK, LDX )
350 CALL SGEMM( 'conjugate transpose
', 'no transpose
', M-P, M-Q, M-P,
351 $ ONE, U2, LDU2, WORK, LDX, ZERO, XF(P+1,Q+1), LDX )
353 DO I = 1, MIN(M-P,M-Q)-R
354 XF(P+I,Q+I) = XF(P+I,Q+I) - ONE
357 XF(P+(MIN(M-P,M-Q)-R)+I,Q+(MIN(M-P,M-Q)-R)+I) =
358 $ XF(P+(MIN(M-P,M-Q)-R)+I,Q+(MIN(M-P,M-Q)-R)+I) -
364 RESID = SLANGE( '1', p, q, xf, ldx, rwork )
365 result( 1 ) = ( resid / real(
max(1,p,q)) ) / eps2
369 resid = slange(
'1', p, m-q, xf(1,q+1), ldx, rwork )
370 result( 2 ) = ( resid / real(
max(1,p,m-q)) ) / eps2
374 resid = slange(
'1', m-p, q, xf(p+1,1), ldx, rwork )
375 result( 3 ) = ( resid / real(
max(1,m-p,q)) ) / eps2
379 resid = slange(
'1', m-p, m-q, xf(p+1,q+1), ldx, rwork )
380 result( 4 ) = ( resid / real(
max(1,m-p,m-q)) ) / eps2
384 CALL slaset(
'Full', p, p, zero, one, work, ldu1 )
385 CALL ssyrk(
'Upper',
'Conjugate transpose', p, p, -one, u1, ldu1,
390 resid = slansy(
'1',
'Upper', p, work, ldu1, rwork )
391 result( 5 ) = ( resid / real(
max(1,p)) ) / ulp
395 CALL slaset(
'Full', m-p, m-p, zero, one, work, ldu2 )
396 CALL ssyrk(
'Upper',
'Conjugate transpose', m-p, m-p, -one, u2,
397 $ ldu2, one, work, ldu2 )
401 resid = slansy(
'1',
'Upper', m-p, work, ldu2, rwork )
402 result( 6 ) = ( resid / real(
max(1,m-p)) ) / ulp
406 CALL slaset(
'Full', q, q, zero, one, work, ldv1t )
407 CALL ssyrk(
'Upper',
'No transpose', q, q, -one, v1t, ldv1t, one,
412 resid = slansy(
'1',
'Upper', q, work, ldv1t, rwork )
413 result( 7 ) = ( resid / real(
max(1,q)) ) / ulp
417 CALL slaset(
'Full', m-q, m-q, zero, one, work, ldv2t )
418 CALL ssyrk(
'Upper',
'No transpose', m-q, m-q, -one, v2t, ldv2t,
423 resid = slansy(
'1',
'Upper', m-q, work, ldv2t, rwork )
424 result( 8 ) = ( resid / real(
max(1,m-q)) ) / ulp
428 result( 9 ) = realzero
430 IF( theta(i).LT.realzero .OR. theta(i).GT.piover2 )
THEN
434 IF ( theta(i).LT.theta(i-1) )
THEN
442 CALL slaset(
'Full', q, q, zero, one, work, ldx )
443 CALL ssyrk(
'Upper',
'Conjugate transpose', q, m, -one, x, ldx,
447 $ slange(
'1', q, q, work, ldx, rwork ) / real( m ) )
451 r =
min( p, m-p, q, m-q )
455 CALL slacpy(
'Full', m, q, x, ldx, xf, ldx )
459 CALL sorcsd2by1(
'Y',
'Y',
'Y', m, p, q, xf(1,1), ldx, xf(p+1,1),
460 $ ldx, theta, u1, ldu1, u2, ldu2, v1t, ldv1t, work,
461 $ lwork, iwork, info )
465 CALL sgemm(
'No transpose',
'Conjugate transpose', p, q, q, one,
466 $ x, ldx, v1t, ldv1t, zero, work, ldx )
468 CALL sgemm(
'Conjugate transpose',
'No transpose', p, q, p, one,
469 $ u1, ldu1, work, ldx, zero, x, ldx )
472 x(i,i) = x(i,i) - one
475 x(
min(p,q)-r+i,
min(p,q)-r+i) =
476 $ x(
min(p,q)-r+i,
min(p,q)-r+i) - cos(theta(i))
479 CALL sgemm(
'No transpose',
'Conjugate transpose', m-p, q, q, one,
480 $ x(p+1,1), ldx, v1t, ldv1t, zero, work, ldx )
482 CALL sgemm(
'Conjugate transpose',
'No transpose', m-p, q, m-p,
483 $ one, u2, ldu2, work, ldx, zero, x(p+1,1), ldx )
485 DO i = 1,
min(m-p,q)-r
486 x(m-i+1,q-i+1) = x(m-i+1,q-i+1) - one
489 x(m-(
min(m-p,q)-r)+1-i,q-(
min(m-p,q)-r)+1-i) =
490 $ x(m-(
min(m-p,q)-r)+1-i,q-(
min(m-p,q)-r)+1-i) -
496 resid = slange(
'1', p, q, x, ldx, rwork )
497 result( 10 ) = ( resid / real(
max(1,p,q)) ) / eps2
501 resid = slange(
'1', m-p, q, x(p+1,1), ldx, rwork )
502 result( 11 ) = ( resid / real(
max(1,m-p,q)) ) / eps2
506 CALL slaset(
'Full', p, p, zero, one, work, ldu1 )
507 CALL ssyrk(
'Upper',
'Conjugate transpose', p, p, -one, u1, ldu1,
512 resid = slansy(
'1',
'Upper', p, work, ldu1, rwork )
513 result( 12 ) = ( resid / real(
max(1,p)) ) / ulp
517 CALL slaset(
'Full', m-p, m-p, zero, one, work, ldu2 )
518 CALL ssyrk(
'Upper',
'Conjugate transpose', m-p, m-p, -one, u2,
519 $ ldu2, one, work, ldu2 )
523 resid = slansy(
'1',
'Upper', m-p, work, ldu2, rwork )
524 result( 13 ) = ( resid / real(
max(1,m-p)) ) / ulp
528 CALL slaset(
'Full', q, q, zero, one, work, ldv1t )
529 CALL ssyrk(
'Upper',
'No transpose', q, q, -one, v1t, ldv1t, one,
534 resid = slansy(
'1',
'Upper', q, work, ldv1t, rwork )
535 result( 14 ) = ( resid / real(
max(1,q)) ) / ulp
539 result( 15 ) = realzero
541 IF( theta(i).LT.realzero .OR. theta(i).GT.piover2 )
THEN
542 result( 15 ) = ulpinv
545 IF ( theta(i).LT.theta(i-1) )
THEN
546 result( 15 ) = ulpinv