source: pacpussensors/trunk/Vislab/lib3dv-1.2.0/lib3dv/eigen/lapack/zlarfb.f@ 141

Last change on this file since 141 was 136, checked in by ldecherf, 8 years ago

Doc
File size: 22.9 KB
Line 
1*> \brief \b ZLARFB
2*
3* =========== DOCUMENTATION ===========
4*
5* Online html documentation available at
6* http://www.netlib.org/lapack/explore-html/
7*
8*> \htmlonly
9*> Download ZLARFB + dependencies
10*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlarfb.f">
11*> [TGZ]</a>
12*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlarfb.f">
13*> [ZIP]</a>
14*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlarfb.f">
15*> [TXT]</a>
16*> \endhtmlonly
17*
18* Definition:
19* ===========
20*
21* SUBROUTINE ZLARFB( SIDE, TRANS, DIRECT, STOREV, M, N, K, V, LDV,
22* T, LDT, C, LDC, WORK, LDWORK )
23*
24* .. Scalar Arguments ..
25* CHARACTER DIRECT, SIDE, STOREV, TRANS
26* INTEGER K, LDC, LDT, LDV, LDWORK, M, N
27* ..
28* .. Array Arguments ..
29* COMPLEX*16 C( LDC, * ), T( LDT, * ), V( LDV, * ),
30* $ WORK( LDWORK, * )
31* ..
32*
33*
34*> \par Purpose:
35* =============
36*>
37*> \verbatim
38*>
39*> ZLARFB applies a complex block reflector H or its transpose H**H to a
40*> complex M-by-N matrix C, from either the left or the right.
41*> \endverbatim
42*
43* Arguments:
44* ==========
45*
46*> \param[in] SIDE
47*> \verbatim
48*> SIDE is CHARACTER*1
49*> = 'L': apply H or H**H from the Left
50*> = 'R': apply H or H**H from the Right
51*> \endverbatim
52*>
53*> \param[in] TRANS
54*> \verbatim
55*> TRANS is CHARACTER*1
56*> = 'N': apply H (No transpose)
57*> = 'C': apply H**H (Conjugate transpose)
58*> \endverbatim
59*>
60*> \param[in] DIRECT
61*> \verbatim
62*> DIRECT is CHARACTER*1
63*> Indicates how H is formed from a product of elementary
64*> reflectors
65*> = 'F': H = H(1) H(2) . . . H(k) (Forward)
66*> = 'B': H = H(k) . . . H(2) H(1) (Backward)
67*> \endverbatim
68*>
69*> \param[in] STOREV
70*> \verbatim
71*> STOREV is CHARACTER*1
72*> Indicates how the vectors which define the elementary
73*> reflectors are stored:
74*> = 'C': Columnwise
75*> = 'R': Rowwise
76*> \endverbatim
77*>
78*> \param[in] M
79*> \verbatim
80*> M is INTEGER
81*> The number of rows of the matrix C.
82*> \endverbatim
83*>
84*> \param[in] N
85*> \verbatim
86*> N is INTEGER
87*> The number of columns of the matrix C.
88*> \endverbatim
89*>
90*> \param[in] K
91*> \verbatim
92*> K is INTEGER
93*> The order of the matrix T (= the number of elementary
94*> reflectors whose product defines the block reflector).
95*> \endverbatim
96*>
97*> \param[in] V
98*> \verbatim
99*> V is COMPLEX*16 array, dimension
100*> (LDV,K) if STOREV = 'C'
101*> (LDV,M) if STOREV = 'R' and SIDE = 'L'
102*> (LDV,N) if STOREV = 'R' and SIDE = 'R'
103*> See Further Details.
104*> \endverbatim
105*>
106*> \param[in] LDV
107*> \verbatim
108*> LDV is INTEGER
109*> The leading dimension of the array V.
110*> If STOREV = 'C' and SIDE = 'L', LDV >= max(1,M);
111*> if STOREV = 'C' and SIDE = 'R', LDV >= max(1,N);
112*> if STOREV = 'R', LDV >= K.
113*> \endverbatim
114*>
115*> \param[in] T
116*> \verbatim
117*> T is COMPLEX*16 array, dimension (LDT,K)
118*> The triangular K-by-K matrix T in the representation of the
119*> block reflector.
120*> \endverbatim
121*>
122*> \param[in] LDT
123*> \verbatim
124*> LDT is INTEGER
125*> The leading dimension of the array T. LDT >= K.
126*> \endverbatim
127*>
128*> \param[in,out] C
129*> \verbatim
130*> C is COMPLEX*16 array, dimension (LDC,N)
131*> On entry, the M-by-N matrix C.
132*> On exit, C is overwritten by H*C or H**H*C or C*H or C*H**H.
133*> \endverbatim
134*>
135*> \param[in] LDC
136*> \verbatim
137*> LDC is INTEGER
138*> The leading dimension of the array C. LDC >= max(1,M).
139*> \endverbatim
140*>
141*> \param[out] WORK
142*> \verbatim
143*> WORK is COMPLEX*16 array, dimension (LDWORK,K)
144*> \endverbatim
145*>
146*> \param[in] LDWORK
147*> \verbatim
148*> LDWORK is INTEGER
149*> The leading dimension of the array WORK.
150*> If SIDE = 'L', LDWORK >= max(1,N);
151*> if SIDE = 'R', LDWORK >= max(1,M).
152*> \endverbatim
153*
154* Authors:
155* ========
156*
157*> \author Univ. of Tennessee
158*> \author Univ. of California Berkeley
159*> \author Univ. of Colorado Denver
160*> \author NAG Ltd.
161*
162*> \date November 2011
163*
164*> \ingroup complex16OTHERauxiliary
165*
166*> \par Further Details:
167* =====================
168*>
169*> \verbatim
170*>
171*> The shape of the matrix V and the storage of the vectors which define
172*> the H(i) is best illustrated by the following example with n = 5 and
173*> k = 3. The elements equal to 1 are not stored; the corresponding
174*> array elements are modified but restored on exit. The rest of the
175*> array is not used.
176*>
177*> DIRECT = 'F' and STOREV = 'C': DIRECT = 'F' and STOREV = 'R':
178*>
179*> V = ( 1 ) V = ( 1 v1 v1 v1 v1 )
180*> ( v1 1 ) ( 1 v2 v2 v2 )
181*> ( v1 v2 1 ) ( 1 v3 v3 )
182*> ( v1 v2 v3 )
183*> ( v1 v2 v3 )
184*>
185*> DIRECT = 'B' and STOREV = 'C': DIRECT = 'B' and STOREV = 'R':
186*>
187*> V = ( v1 v2 v3 ) V = ( v1 v1 1 )
188*> ( v1 v2 v3 ) ( v2 v2 v2 1 )
189*> ( 1 v2 v3 ) ( v3 v3 v3 v3 1 )
190*> ( 1 v3 )
191*> ( 1 )
192*> \endverbatim
193*>
194* =====================================================================
195 SUBROUTINE ZLARFB( SIDE, TRANS, DIRECT, STOREV, M, N, K, V, LDV,
196 $ T, LDT, C, LDC, WORK, LDWORK )
197*
198* -- LAPACK auxiliary routine (version 3.4.0) --
199* -- LAPACK is a software package provided by Univ. of Tennessee, --
200* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
201* November 2011
202*
203* .. Scalar Arguments ..
204 CHARACTER DIRECT, SIDE, STOREV, TRANS
205 INTEGER K, LDC, LDT, LDV, LDWORK, M, N
206* ..
207* .. Array Arguments ..
208 COMPLEX*16 C( LDC, * ), T( LDT, * ), V( LDV, * ),
209 $ WORK( LDWORK, * )
210* ..
211*
212* =====================================================================
213*
214* .. Parameters ..
215 COMPLEX*16 ONE
216 PARAMETER ( ONE = ( 1.0D+0, 0.0D+0 ) )
217* ..
218* .. Local Scalars ..
219 CHARACTER TRANST
220 INTEGER I, J, LASTV, LASTC
221* ..
222* .. External Functions ..
223 LOGICAL LSAME
224 INTEGER ILAZLR, ILAZLC
225 EXTERNAL LSAME, ILAZLR, ILAZLC
226* ..
227* .. External Subroutines ..
228 EXTERNAL ZCOPY, ZGEMM, ZLACGV, ZTRMM
229* ..
230* .. Intrinsic Functions ..
231 INTRINSIC DCONJG
232* ..
233* .. Executable Statements ..
234*
235* Quick return if possible
236*
237 IF( M.LE.0 .OR. N.LE.0 )
238 $ RETURN
239*
240 IF( LSAME( TRANS, 'N' ) ) THEN
241 TRANST = 'C'
242 ELSE
243 TRANST = 'N'
244 END IF
245*
246 IF( LSAME( STOREV, 'C' ) ) THEN
247*
248 IF( LSAME( DIRECT, 'F' ) ) THEN
249*
250* Let V = ( V1 ) (first K rows)
251* ( V2 )
252* where V1 is unit lower triangular.
253*
254 IF( LSAME( SIDE, 'L' ) ) THEN
255*
256* Form H * C or H**H * C where C = ( C1 )
257* ( C2 )
258*
259 LASTV = MAX( K, ILAZLR( M, K, V, LDV ) )
260 LASTC = ILAZLC( LASTV, N, C, LDC )
261*
262* W := C**H * V = (C1**H * V1 + C2**H * V2) (stored in WORK)
263*
264* W := C1**H
265*
266 DO 10 J = 1, K
267 CALL ZCOPY( LASTC, C( J, 1 ), LDC, WORK( 1, J ), 1 )
268 CALL ZLACGV( LASTC, WORK( 1, J ), 1 )
269 10 CONTINUE
270*
271* W := W * V1
272*
273 CALL ZTRMM( 'Right', 'Lower', 'No transpose', 'Unit',
274 $ LASTC, K, ONE, V, LDV, WORK, LDWORK )
275 IF( LASTV.GT.K ) THEN
276*
277* W := W + C2**H *V2
278*
279 CALL ZGEMM( 'Conjugate transpose', 'No transpose',
280 $ LASTC, K, LASTV-K, ONE, C( K+1, 1 ), LDC,
281 $ V( K+1, 1 ), LDV, ONE, WORK, LDWORK )
282 END IF
283*
284* W := W * T**H or W * T
285*
286 CALL ZTRMM( 'Right', 'Upper', TRANST, 'Non-unit',
287 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
288*
289* C := C - V * W**H
290*
291 IF( M.GT.K ) THEN
292*
293* C2 := C2 - V2 * W**H
294*
295 CALL ZGEMM( 'No transpose', 'Conjugate transpose',
296 $ LASTV-K, LASTC, K,
297 $ -ONE, V( K+1, 1 ), LDV, WORK, LDWORK,
298 $ ONE, C( K+1, 1 ), LDC )
299 END IF
300*
301* W := W * V1**H
302*
303 CALL ZTRMM( 'Right', 'Lower', 'Conjugate transpose',
304 $ 'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK )
305*
306* C1 := C1 - W**H
307*
308 DO 30 J = 1, K
309 DO 20 I = 1, LASTC
310 C( J, I ) = C( J, I ) - DCONJG( WORK( I, J ) )
311 20 CONTINUE
312 30 CONTINUE
313*
314 ELSE IF( LSAME( SIDE, 'R' ) ) THEN
315*
316* Form C * H or C * H**H where C = ( C1 C2 )
317*
318 LASTV = MAX( K, ILAZLR( N, K, V, LDV ) )
319 LASTC = ILAZLR( M, LASTV, C, LDC )
320*
321* W := C * V = (C1*V1 + C2*V2) (stored in WORK)
322*
323* W := C1
324*
325 DO 40 J = 1, K
326 CALL ZCOPY( LASTC, C( 1, J ), 1, WORK( 1, J ), 1 )
327 40 CONTINUE
328*
329* W := W * V1
330*
331 CALL ZTRMM( 'Right', 'Lower', 'No transpose', 'Unit',
332 $ LASTC, K, ONE, V, LDV, WORK, LDWORK )
333 IF( LASTV.GT.K ) THEN
334*
335* W := W + C2 * V2
336*
337 CALL ZGEMM( 'No transpose', 'No transpose',
338 $ LASTC, K, LASTV-K,
339 $ ONE, C( 1, K+1 ), LDC, V( K+1, 1 ), LDV,
340 $ ONE, WORK, LDWORK )
341 END IF
342*
343* W := W * T or W * T**H
344*
345 CALL ZTRMM( 'Right', 'Upper', TRANS, 'Non-unit',
346 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
347*
348* C := C - W * V**H
349*
350 IF( LASTV.GT.K ) THEN
351*
352* C2 := C2 - W * V2**H
353*
354 CALL ZGEMM( 'No transpose', 'Conjugate transpose',
355 $ LASTC, LASTV-K, K,
356 $ -ONE, WORK, LDWORK, V( K+1, 1 ), LDV,
357 $ ONE, C( 1, K+1 ), LDC )
358 END IF
359*
360* W := W * V1**H
361*
362 CALL ZTRMM( 'Right', 'Lower', 'Conjugate transpose',
363 $ 'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK )
364*
365* C1 := C1 - W
366*
367 DO 60 J = 1, K
368 DO 50 I = 1, LASTC
369 C( I, J ) = C( I, J ) - WORK( I, J )
370 50 CONTINUE
371 60 CONTINUE
372 END IF
373*
374 ELSE
375*
376* Let V = ( V1 )
377* ( V2 ) (last K rows)
378* where V2 is unit upper triangular.
379*
380 IF( LSAME( SIDE, 'L' ) ) THEN
381*
382* Form H * C or H**H * C where C = ( C1 )
383* ( C2 )
384*
385 LASTV = MAX( K, ILAZLR( M, K, V, LDV ) )
386 LASTC = ILAZLC( LASTV, N, C, LDC )
387*
388* W := C**H * V = (C1**H * V1 + C2**H * V2) (stored in WORK)
389*
390* W := C2**H
391*
392 DO 70 J = 1, K
393 CALL ZCOPY( LASTC, C( LASTV-K+J, 1 ), LDC,
394 $ WORK( 1, J ), 1 )
395 CALL ZLACGV( LASTC, WORK( 1, J ), 1 )
396 70 CONTINUE
397*
398* W := W * V2
399*
400 CALL ZTRMM( 'Right', 'Upper', 'No transpose', 'Unit',
401 $ LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV,
402 $ WORK, LDWORK )
403 IF( LASTV.GT.K ) THEN
404*
405* W := W + C1**H*V1
406*
407 CALL ZGEMM( 'Conjugate transpose', 'No transpose',
408 $ LASTC, K, LASTV-K,
409 $ ONE, C, LDC, V, LDV,
410 $ ONE, WORK, LDWORK )
411 END IF
412*
413* W := W * T**H or W * T
414*
415 CALL ZTRMM( 'Right', 'Lower', TRANST, 'Non-unit',
416 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
417*
418* C := C - V * W**H
419*
420 IF( LASTV.GT.K ) THEN
421*
422* C1 := C1 - V1 * W**H
423*
424 CALL ZGEMM( 'No transpose', 'Conjugate transpose',
425 $ LASTV-K, LASTC, K,
426 $ -ONE, V, LDV, WORK, LDWORK,
427 $ ONE, C, LDC )
428 END IF
429*
430* W := W * V2**H
431*
432 CALL ZTRMM( 'Right', 'Upper', 'Conjugate transpose',
433 $ 'Unit', LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV,
434 $ WORK, LDWORK )
435*
436* C2 := C2 - W**H
437*
438 DO 90 J = 1, K
439 DO 80 I = 1, LASTC
440 C( LASTV-K+J, I ) = C( LASTV-K+J, I ) -
441 $ DCONJG( WORK( I, J ) )
442 80 CONTINUE
443 90 CONTINUE
444*
445 ELSE IF( LSAME( SIDE, 'R' ) ) THEN
446*
447* Form C * H or C * H**H where C = ( C1 C2 )
448*
449 LASTV = MAX( K, ILAZLR( N, K, V, LDV ) )
450 LASTC = ILAZLR( M, LASTV, C, LDC )
451*
452* W := C * V = (C1*V1 + C2*V2) (stored in WORK)
453*
454* W := C2
455*
456 DO 100 J = 1, K
457 CALL ZCOPY( LASTC, C( 1, LASTV-K+J ), 1,
458 $ WORK( 1, J ), 1 )
459 100 CONTINUE
460*
461* W := W * V2
462*
463 CALL ZTRMM( 'Right', 'Upper', 'No transpose', 'Unit',
464 $ LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV,
465 $ WORK, LDWORK )
466 IF( LASTV.GT.K ) THEN
467*
468* W := W + C1 * V1
469*
470 CALL ZGEMM( 'No transpose', 'No transpose',
471 $ LASTC, K, LASTV-K,
472 $ ONE, C, LDC, V, LDV, ONE, WORK, LDWORK )
473 END IF
474*
475* W := W * T or W * T**H
476*
477 CALL ZTRMM( 'Right', 'Lower', TRANS, 'Non-unit',
478 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
479*
480* C := C - W * V**H
481*
482 IF( LASTV.GT.K ) THEN
483*
484* C1 := C1 - W * V1**H
485*
486 CALL ZGEMM( 'No transpose', 'Conjugate transpose',
487 $ LASTC, LASTV-K, K, -ONE, WORK, LDWORK, V, LDV,
488 $ ONE, C, LDC )
489 END IF
490*
491* W := W * V2**H
492*
493 CALL ZTRMM( 'Right', 'Upper', 'Conjugate transpose',
494 $ 'Unit', LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV,
495 $ WORK, LDWORK )
496*
497* C2 := C2 - W
498*
499 DO 120 J = 1, K
500 DO 110 I = 1, LASTC
501 C( I, LASTV-K+J ) = C( I, LASTV-K+J )
502 $ - WORK( I, J )
503 110 CONTINUE
504 120 CONTINUE
505 END IF
506 END IF
507*
508 ELSE IF( LSAME( STOREV, 'R' ) ) THEN
509*
510 IF( LSAME( DIRECT, 'F' ) ) THEN
511*
512* Let V = ( V1 V2 ) (V1: first K columns)
513* where V1 is unit upper triangular.
514*
515 IF( LSAME( SIDE, 'L' ) ) THEN
516*
517* Form H * C or H**H * C where C = ( C1 )
518* ( C2 )
519*
520 LASTV = MAX( K, ILAZLC( K, M, V, LDV ) )
521 LASTC = ILAZLC( LASTV, N, C, LDC )
522*
523* W := C**H * V**H = (C1**H * V1**H + C2**H * V2**H) (stored in WORK)
524*
525* W := C1**H
526*
527 DO 130 J = 1, K
528 CALL ZCOPY( LASTC, C( J, 1 ), LDC, WORK( 1, J ), 1 )
529 CALL ZLACGV( LASTC, WORK( 1, J ), 1 )
530 130 CONTINUE
531*
532* W := W * V1**H
533*
534 CALL ZTRMM( 'Right', 'Upper', 'Conjugate transpose',
535 $ 'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK )
536 IF( LASTV.GT.K ) THEN
537*
538* W := W + C2**H*V2**H
539*
540 CALL ZGEMM( 'Conjugate transpose',
541 $ 'Conjugate transpose', LASTC, K, LASTV-K,
542 $ ONE, C( K+1, 1 ), LDC, V( 1, K+1 ), LDV,
543 $ ONE, WORK, LDWORK )
544 END IF
545*
546* W := W * T**H or W * T
547*
548 CALL ZTRMM( 'Right', 'Upper', TRANST, 'Non-unit',
549 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
550*
551* C := C - V**H * W**H
552*
553 IF( LASTV.GT.K ) THEN
554*
555* C2 := C2 - V2**H * W**H
556*
557 CALL ZGEMM( 'Conjugate transpose',
558 $ 'Conjugate transpose', LASTV-K, LASTC, K,
559 $ -ONE, V( 1, K+1 ), LDV, WORK, LDWORK,
560 $ ONE, C( K+1, 1 ), LDC )
561 END IF
562*
563* W := W * V1
564*
565 CALL ZTRMM( 'Right', 'Upper', 'No transpose', 'Unit',
566 $ LASTC, K, ONE, V, LDV, WORK, LDWORK )
567*
568* C1 := C1 - W**H
569*
570 DO 150 J = 1, K
571 DO 140 I = 1, LASTC
572 C( J, I ) = C( J, I ) - DCONJG( WORK( I, J ) )
573 140 CONTINUE
574 150 CONTINUE
575*
576 ELSE IF( LSAME( SIDE, 'R' ) ) THEN
577*
578* Form C * H or C * H**H where C = ( C1 C2 )
579*
580 LASTV = MAX( K, ILAZLC( K, N, V, LDV ) )
581 LASTC = ILAZLR( M, LASTV, C, LDC )
582*
583* W := C * V**H = (C1*V1**H + C2*V2**H) (stored in WORK)
584*
585* W := C1
586*
587 DO 160 J = 1, K
588 CALL ZCOPY( LASTC, C( 1, J ), 1, WORK( 1, J ), 1 )
589 160 CONTINUE
590*
591* W := W * V1**H
592*
593 CALL ZTRMM( 'Right', 'Upper', 'Conjugate transpose',
594 $ 'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK )
595 IF( LASTV.GT.K ) THEN
596*
597* W := W + C2 * V2**H
598*
599 CALL ZGEMM( 'No transpose', 'Conjugate transpose',
600 $ LASTC, K, LASTV-K, ONE, C( 1, K+1 ), LDC,
601 $ V( 1, K+1 ), LDV, ONE, WORK, LDWORK )
602 END IF
603*
604* W := W * T or W * T**H
605*
606 CALL ZTRMM( 'Right', 'Upper', TRANS, 'Non-unit',
607 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
608*
609* C := C - W * V
610*
611 IF( LASTV.GT.K ) THEN
612*
613* C2 := C2 - W * V2
614*
615 CALL ZGEMM( 'No transpose', 'No transpose',
616 $ LASTC, LASTV-K, K,
617 $ -ONE, WORK, LDWORK, V( 1, K+1 ), LDV,
618 $ ONE, C( 1, K+1 ), LDC )
619 END IF
620*
621* W := W * V1
622*
623 CALL ZTRMM( 'Right', 'Upper', 'No transpose', 'Unit',
624 $ LASTC, K, ONE, V, LDV, WORK, LDWORK )
625*
626* C1 := C1 - W
627*
628 DO 180 J = 1, K
629 DO 170 I = 1, LASTC
630 C( I, J ) = C( I, J ) - WORK( I, J )
631 170 CONTINUE
632 180 CONTINUE
633*
634 END IF
635*
636 ELSE
637*
638* Let V = ( V1 V2 ) (V2: last K columns)
639* where V2 is unit lower triangular.
640*
641 IF( LSAME( SIDE, 'L' ) ) THEN
642*
643* Form H * C or H**H * C where C = ( C1 )
644* ( C2 )
645*
646 LASTV = MAX( K, ILAZLC( K, M, V, LDV ) )
647 LASTC = ILAZLC( LASTV, N, C, LDC )
648*
649* W := C**H * V**H = (C1**H * V1**H + C2**H * V2**H) (stored in WORK)
650*
651* W := C2**H
652*
653 DO 190 J = 1, K
654 CALL ZCOPY( LASTC, C( LASTV-K+J, 1 ), LDC,
655 $ WORK( 1, J ), 1 )
656 CALL ZLACGV( LASTC, WORK( 1, J ), 1 )
657 190 CONTINUE
658*
659* W := W * V2**H
660*
661 CALL ZTRMM( 'Right', 'Lower', 'Conjugate transpose',
662 $ 'Unit', LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV,
663 $ WORK, LDWORK )
664 IF( LASTV.GT.K ) THEN
665*
666* W := W + C1**H * V1**H
667*
668 CALL ZGEMM( 'Conjugate transpose',
669 $ 'Conjugate transpose', LASTC, K, LASTV-K,
670 $ ONE, C, LDC, V, LDV, ONE, WORK, LDWORK )
671 END IF
672*
673* W := W * T**H or W * T
674*
675 CALL ZTRMM( 'Right', 'Lower', TRANST, 'Non-unit',
676 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
677*
678* C := C - V**H * W**H
679*
680 IF( LASTV.GT.K ) THEN
681*
682* C1 := C1 - V1**H * W**H
683*
684 CALL ZGEMM( 'Conjugate transpose',
685 $ 'Conjugate transpose', LASTV-K, LASTC, K,
686 $ -ONE, V, LDV, WORK, LDWORK, ONE, C, LDC )
687 END IF
688*
689* W := W * V2
690*
691 CALL ZTRMM( 'Right', 'Lower', 'No transpose', 'Unit',
692 $ LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV,
693 $ WORK, LDWORK )
694*
695* C2 := C2 - W**H
696*
697 DO 210 J = 1, K
698 DO 200 I = 1, LASTC
699 C( LASTV-K+J, I ) = C( LASTV-K+J, I ) -
700 $ DCONJG( WORK( I, J ) )
701 200 CONTINUE
702 210 CONTINUE
703*
704 ELSE IF( LSAME( SIDE, 'R' ) ) THEN
705*
706* Form C * H or C * H**H where C = ( C1 C2 )
707*
708 LASTV = MAX( K, ILAZLC( K, N, V, LDV ) )
709 LASTC = ILAZLR( M, LASTV, C, LDC )
710*
711* W := C * V**H = (C1*V1**H + C2*V2**H) (stored in WORK)
712*
713* W := C2
714*
715 DO 220 J = 1, K
716 CALL ZCOPY( LASTC, C( 1, LASTV-K+J ), 1,
717 $ WORK( 1, J ), 1 )
718 220 CONTINUE
719*
720* W := W * V2**H
721*
722 CALL ZTRMM( 'Right', 'Lower', 'Conjugate transpose',
723 $ 'Unit', LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV,
724 $ WORK, LDWORK )
725 IF( LASTV.GT.K ) THEN
726*
727* W := W + C1 * V1**H
728*
729 CALL ZGEMM( 'No transpose', 'Conjugate transpose',
730 $ LASTC, K, LASTV-K, ONE, C, LDC, V, LDV, ONE,
731 $ WORK, LDWORK )
732 END IF
733*
734* W := W * T or W * T**H
735*
736 CALL ZTRMM( 'Right', 'Lower', TRANS, 'Non-unit',
737 $ LASTC, K, ONE, T, LDT, WORK, LDWORK )
738*
739* C := C - W * V
740*
741 IF( LASTV.GT.K ) THEN
742*
743* C1 := C1 - W * V1
744*
745 CALL ZGEMM( 'No transpose', 'No transpose',
746 $ LASTC, LASTV-K, K, -ONE, WORK, LDWORK, V, LDV,
747 $ ONE, C, LDC )
748 END IF
749*
750* W := W * V2
751*
752 CALL ZTRMM( 'Right', 'Lower', 'No transpose', 'Unit',
753 $ LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV,
754 $ WORK, LDWORK )
755*
756* C1 := C1 - W
757*
758 DO 240 J = 1, K
759 DO 230 I = 1, LASTC
760 C( I, LASTV-K+J ) = C( I, LASTV-K+J )
761 $ - WORK( I, J )
762 230 CONTINUE
763 240 CONTINUE
764*
765 END IF
766*
767 END IF
768 END IF
769*
770 RETURN
771*
772* End of ZLARFB
773*
774 END
Note: See TracBrowser for help on using the repository browser.