LAPACK 3.12.1
LAPACK: Linear Algebra PACKage
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ilaenv.f
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1*> \brief \b ILAENV
2*
3* =========== DOCUMENTATION ===========
4*
5* Online html documentation available at
6* http://www.netlib.org/lapack/explore-html/
7*
8*> Download ILAENV + dependencies
9*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/ilaenv.f">
10*> [TGZ]</a>
11*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/ilaenv.f">
12*> [ZIP]</a>
13*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/ilaenv.f">
14*> [TXT]</a>
15*
16* Definition:
17* ===========
18*
19* INTEGER FUNCTION ILAENV( ISPEC, NAME, OPTS, N1, N2, N3, N4 )
20*
21* .. Scalar Arguments ..
22* CHARACTER*( * ) NAME, OPTS
23* INTEGER ISPEC, N1, N2, N3, N4
24* ..
25*
26*
27*> \par Purpose:
28* =============
29*>
30*> \verbatim
31*>
32*> ILAENV is called from the LAPACK routines to choose problem-dependent
33*> parameters for the local environment. See ISPEC for a description of
34*> the parameters.
35*>
36*> ILAENV returns an INTEGER
37*> if ILAENV >= 0: ILAENV returns the value of the parameter specified by ISPEC
38*> if ILAENV < 0: if ILAENV = -k, the k-th argument had an illegal value.
39*>
40*> This version provides a set of parameters which should give good,
41*> but not optimal, performance on many of the currently available
42*> computers. Users are encouraged to modify this subroutine to set
43*> the tuning parameters for their particular machine using the option
44*> and problem size information in the arguments.
45*>
46*> This routine will not function correctly if it is converted to all
47*> lower case. Converting it to all upper case is allowed.
48*> \endverbatim
49*
50* Arguments:
51* ==========
52*
53*> \param[in] ISPEC
54*> \verbatim
55*> ISPEC is INTEGER
56*> Specifies the parameter to be returned as the value of
57*> ILAENV.
58*> = 1: the optimal blocksize; if this value is 1, an unblocked
59*> algorithm will give the best performance.
60*> = 2: the minimum block size for which the block routine
61*> should be used; if the usable block size is less than
62*> this value, an unblocked routine should be used.
63*> = 3: the crossover point (in a block routine, for N less
64*> than this value, an unblocked routine should be used)
65*> = 4: the number of shifts, used in the nonsymmetric
66*> eigenvalue routines (DEPRECATED)
67*> = 5: the minimum column dimension for blocking to be used;
68*> rectangular blocks must have dimension at least k by m,
69*> where k is given by ILAENV(2,...) and m by ILAENV(5,...)
70*> = 6: the crossover point for the SVD (when reducing an m by n
71*> matrix to bidiagonal form, if max(m,n)/min(m,n) exceeds
72*> this value, a QR factorization is used first to reduce
73*> the matrix to a triangular form.)
74*> = 7: the number of processors
75*> = 8: the crossover point for the multishift QR method
76*> for nonsymmetric eigenvalue problems (DEPRECATED)
77*> = 9: maximum size of the subproblems at the bottom of the
78*> computation tree in the divide-and-conquer algorithm
79*> (used by xGELSD and xGESDD)
80*> =10: ieee infinity and NaN arithmetic can be trusted not to trap
81*> =11: infinity arithmetic can be trusted not to trap
82*> 12 <= ISPEC <= 17:
83*> xHSEQR or related subroutines,
84*> see IPARMQ for detailed explanation
85*> \endverbatim
86*>
87*> \param[in] NAME
88*> \verbatim
89*> NAME is CHARACTER*(*)
90*> The name of the calling subroutine, in either upper case or
91*> lower case.
92*> \endverbatim
93*>
94*> \param[in] OPTS
95*> \verbatim
96*> OPTS is CHARACTER*(*)
97*> The character options to the subroutine NAME, concatenated
98*> into a single character string. For example, UPLO = 'U',
99*> TRANS = 'T', and DIAG = 'N' for a triangular routine would
100*> be specified as OPTS = 'UTN'.
101*> \endverbatim
102*>
103*> \param[in] N1
104*> \verbatim
105*> N1 is INTEGER
106*> \endverbatim
107*>
108*> \param[in] N2
109*> \verbatim
110*> N2 is INTEGER
111*> \endverbatim
112*>
113*> \param[in] N3
114*> \verbatim
115*> N3 is INTEGER
116*> \endverbatim
117*>
118*> \param[in] N4
119*> \verbatim
120*> N4 is INTEGER
121*> Problem dimensions for the subroutine NAME; these may not all
122*> be required.
123*> \endverbatim
124*
125* Authors:
126* ========
127*
128*> \author Univ. of Tennessee
129*> \author Univ. of California Berkeley
130*> \author Univ. of Colorado Denver
131*> \author NAG Ltd.
132*
133*> \ingroup ilaenv
134*
135*> \par Further Details:
136* =====================
137*>
138*> \verbatim
139*>
140*> The following conventions have been used when calling ILAENV from the
141*> LAPACK routines:
142*> 1) OPTS is a concatenation of all of the character options to
143*> subroutine NAME, in the same order that they appear in the
144*> argument list for NAME, even if they are not used in determining
145*> the value of the parameter specified by ISPEC.
146*> 2) The problem dimensions N1, N2, N3, N4 are specified in the order
147*> that they appear in the argument list for NAME. N1 is used
148*> first, N2 second, and so on, and unused problem dimensions are
149*> passed a value of -1.
150*> 3) The parameter value returned by ILAENV is checked for validity in
151*> the calling subroutine. For example, ILAENV is used to retrieve
152*> the optimal blocksize for STRTRI as follows:
153*>
154*> NB = ILAENV( 1, 'STRTRI', UPLO // DIAG, N, -1, -1, -1 )
155*> IF( NB.LE.1 ) NB = MAX( 1, N )
156*> \endverbatim
157*>
158* =====================================================================
159 INTEGER FUNCTION ilaenv( ISPEC, NAME, OPTS, N1, N2, N3, N4 )
160*
161* -- LAPACK auxiliary routine --
162* -- LAPACK is a software package provided by Univ. of Tennessee, --
163* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
164*
165* .. Scalar Arguments ..
166 CHARACTER*( * ) name, opts
167 INTEGER ispec, n1, n2, n3, n4
168* ..
169*
170* =====================================================================
171*
172* .. Local Scalars ..
173 INTEGER i, ic, iz, nb, nbmin, nx
174 LOGICAL cname, sname, twostage
175 CHARACTER c1*1, c2*2, c4*2, c3*3, subnam*16
176* ..
177* .. Intrinsic Functions ..
178 INTRINSIC char, ichar, int, min, real
179* ..
180* .. External Functions ..
181 INTEGER ieeeck, iparmq, iparam2stage
182 EXTERNAL ieeeck, iparmq, iparam2stage
183* ..
184* .. Executable Statements ..
185*
186 GO TO ( 10, 10, 10, 80, 90, 100, 110, 120,
187 $ 130, 140, 150, 160, 160, 160, 160, 160, 160)ispec
188*
189* Invalid value for ISPEC
190*
191 ilaenv = -1
192 RETURN
193*
194 10 CONTINUE
195*
196* Convert NAME to upper case if the first character is lower case.
197*
198 ilaenv = 1
199 subnam = name
200 ic = ichar( subnam( 1: 1 ) )
201 iz = ichar( 'Z' )
202 IF( iz.EQ.90 .OR. iz.EQ.122 ) THEN
203*
204* ASCII character set
205*
206 IF( ic.GE.97 .AND. ic.LE.122 ) THEN
207 subnam( 1: 1 ) = char( ic-32 )
208 DO 20 i = 2, 6
209 ic = ichar( subnam( i: i ) )
210 IF( ic.GE.97 .AND. ic.LE.122 )
211 $ subnam( i: i ) = char( ic-32 )
212 20 CONTINUE
213 END IF
214*
215 ELSE IF( iz.EQ.233 .OR. iz.EQ.169 ) THEN
216*
217* EBCDIC character set
218*
219 IF( ( ic.GE.129 .AND. ic.LE.137 ) .OR.
220 $ ( ic.GE.145 .AND. ic.LE.153 ) .OR.
221 $ ( ic.GE.162 .AND. ic.LE.169 ) ) THEN
222 subnam( 1: 1 ) = char( ic+64 )
223 DO 30 i = 2, 6
224 ic = ichar( subnam( i: i ) )
225 IF( ( ic.GE.129 .AND. ic.LE.137 ) .OR.
226 $ ( ic.GE.145 .AND. ic.LE.153 ) .OR.
227 $ ( ic.GE.162 .AND. ic.LE.169 ) )subnam( i:
228 $ i ) = char( ic+64 )
229 30 CONTINUE
230 END IF
231*
232 ELSE IF( iz.EQ.218 .OR. iz.EQ.250 ) THEN
233*
234* Prime machines: ASCII+128
235*
236 IF( ic.GE.225 .AND. ic.LE.250 ) THEN
237 subnam( 1: 1 ) = char( ic-32 )
238 DO 40 i = 2, 6
239 ic = ichar( subnam( i: i ) )
240 IF( ic.GE.225 .AND. ic.LE.250 )
241 $ subnam( i: i ) = char( ic-32 )
242 40 CONTINUE
243 END IF
244 END IF
245*
246 c1 = subnam( 1: 1 )
247 sname = c1.EQ.'S' .OR. c1.EQ.'D'
248 cname = c1.EQ.'C' .OR. c1.EQ.'Z'
249 IF( .NOT.( cname .OR. sname ) )
250 $ RETURN
251 c2 = subnam( 2: 3 )
252 c3 = subnam( 4: 6 )
253 c4 = c3( 2: 3 )
254 twostage = len( subnam ).GE.11
255 $ .AND. subnam( 11: 11 ).EQ.'2'
256*
257 GO TO ( 50, 60, 70 )ispec
258*
259 50 CONTINUE
260*
261* ISPEC = 1: block size
262*
263* In these examples, separate code is provided for setting NB for
264* real and complex. We assume that NB will take the same value in
265* single or double precision.
266*
267 nb = 1
268*
269 IF( subnam(2:6).EQ.'LAORH' ) THEN
270*
271* This is for *LAORHR_GETRFNP routine
272*
273 IF( sname ) THEN
274 nb = 32
275 ELSE
276 nb = 32
277 END IF
278 ELSE IF( c2.EQ.'GE' ) THEN
279 IF( c3.EQ.'TRF' ) THEN
280 IF( sname ) THEN
281 nb = 64
282 ELSE
283 nb = 64
284 END IF
285 ELSE IF( c3.EQ.'QRF' .OR. c3.EQ.'RQF' .OR. c3.EQ.'LQF' .OR.
286 $ c3.EQ.'QLF' ) THEN
287 IF( sname ) THEN
288 nb = 32
289 ELSE
290 nb = 32
291 END IF
292 ELSE IF( c3.EQ.'QR ') THEN
293 IF( n3 .EQ. 1) THEN
294 IF( sname ) THEN
295* M*N
296 IF ((n1*n2.LE.131072).OR.(n1.LE.8192)) THEN
297 nb = n1
298 ELSE
299 nb = 32768/n2
300 END IF
301 ELSE
302 IF ((n1*n2.LE.131072).OR.(n1.LE.8192)) THEN
303 nb = n1
304 ELSE
305 nb = 32768/n2
306 END IF
307 END IF
308 ELSE
309 IF( sname ) THEN
310 nb = 1
311 ELSE
312 nb = 1
313 END IF
314 END IF
315 ELSE IF( c3.EQ.'LQ ') THEN
316 IF( n3 .EQ. 2) THEN
317 IF( sname ) THEN
318* M*N
319 IF ((n1*n2.LE.131072).OR.(n1.LE.8192)) THEN
320 nb = n1
321 ELSE
322 nb = 32768/n2
323 END IF
324 ELSE
325 IF ((n1*n2.LE.131072).OR.(n1.LE.8192)) THEN
326 nb = n1
327 ELSE
328 nb = 32768/n2
329 END IF
330 END IF
331 ELSE
332 IF( sname ) THEN
333 nb = 1
334 ELSE
335 nb = 1
336 END IF
337 END IF
338 ELSE IF( c3.EQ.'HRD' ) THEN
339 IF( sname ) THEN
340 nb = 32
341 ELSE
342 nb = 32
343 END IF
344 ELSE IF( c3.EQ.'BRD' ) THEN
345 IF( sname ) THEN
346 nb = 32
347 ELSE
348 nb = 32
349 END IF
350 ELSE IF( c3.EQ.'TRI' ) THEN
351 IF( sname ) THEN
352 nb = 64
353 ELSE
354 nb = 64
355 END IF
356 ELSE IF( subnam( 4: 7 ).EQ.'QP3RK' ) THEN
357 IF( sname ) THEN
358 nb = 32
359 ELSE
360 nb = 32
361 END IF
362 END IF
363 ELSE IF( c2.EQ.'PO' ) THEN
364 IF( c3.EQ.'TRF' ) THEN
365 IF( sname ) THEN
366 nb = 64
367 ELSE
368 nb = 64
369 END IF
370 END IF
371 ELSE IF( c2.EQ.'SY' ) THEN
372 IF( c3.EQ.'TRF' ) THEN
373 IF( sname ) THEN
374 IF( twostage ) THEN
375 nb = 192
376 ELSE
377 nb = 64
378 END IF
379 ELSE
380 IF( twostage ) THEN
381 nb = 192
382 ELSE
383 nb = 64
384 END IF
385 END IF
386 ELSE IF( sname .AND. c3.EQ.'TRD' ) THEN
387 nb = 32
388 ELSE IF( sname .AND. c3.EQ.'GST' ) THEN
389 nb = 64
390 END IF
391 ELSE IF( cname .AND. c2.EQ.'HE' ) THEN
392 IF( c3.EQ.'TRF' ) THEN
393 IF( twostage ) THEN
394 nb = 192
395 ELSE
396 nb = 64
397 END IF
398 ELSE IF( c3.EQ.'TRD' ) THEN
399 nb = 32
400 ELSE IF( c3.EQ.'GST' ) THEN
401 nb = 64
402 END IF
403 ELSE IF( sname .AND. c2.EQ.'OR' ) THEN
404 IF( c3( 1: 1 ).EQ.'G' ) THEN
405 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
406 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
407 $ THEN
408 nb = 32
409 END IF
410 ELSE IF( c3( 1: 1 ).EQ.'M' ) THEN
411 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
412 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
413 $ THEN
414 nb = 32
415 END IF
416 END IF
417 ELSE IF( cname .AND. c2.EQ.'UN' ) THEN
418 IF( c3( 1: 1 ).EQ.'G' ) THEN
419 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
420 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
421 $ THEN
422 nb = 32
423 END IF
424 ELSE IF( c3( 1: 1 ).EQ.'M' ) THEN
425 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
426 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
427 $ THEN
428 nb = 32
429 END IF
430 END IF
431 ELSE IF( c2.EQ.'GB' ) THEN
432 IF( c3.EQ.'TRF' ) THEN
433 IF( sname ) THEN
434 IF( n4.LE.64 ) THEN
435 nb = 1
436 ELSE
437 nb = 32
438 END IF
439 ELSE
440 IF( n4.LE.64 ) THEN
441 nb = 1
442 ELSE
443 nb = 32
444 END IF
445 END IF
446 END IF
447 ELSE IF( c2.EQ.'PB' ) THEN
448 IF( c3.EQ.'TRF' ) THEN
449 IF( sname ) THEN
450 IF( n2.LE.64 ) THEN
451 nb = 1
452 ELSE
453 nb = 32
454 END IF
455 ELSE
456 IF( n2.LE.64 ) THEN
457 nb = 1
458 ELSE
459 nb = 32
460 END IF
461 END IF
462 END IF
463 ELSE IF( c2.EQ.'TR' ) THEN
464 IF( c3.EQ.'TRI' ) THEN
465 IF( sname ) THEN
466 nb = 64
467 ELSE
468 nb = 64
469 END IF
470 ELSE IF ( c3.EQ.'EVC' ) THEN
471 IF( sname ) THEN
472 nb = 64
473 ELSE
474 nb = 64
475 END IF
476 ELSE IF( c3.EQ.'SYL' ) THEN
477* The upper bound is to prevent overly aggressive scaling.
478 IF( sname ) THEN
479 nb = min( max( 48, int( ( min( n1, n2 ) * 16 ) / 100) ),
480 $ 240 )
481 ELSE
482 nb = min( max( 24, int( ( min( n1, n2 ) * 8 ) / 100) ),
483 $ 80 )
484 END IF
485 END IF
486 ELSE IF( c2.EQ.'LA' ) THEN
487 IF( c3.EQ.'UUM' ) THEN
488 IF( sname ) THEN
489 nb = 64
490 ELSE
491 nb = 64
492 END IF
493 ELSE IF( c3.EQ.'TRS' ) THEN
494 IF( sname ) THEN
495 nb = 32
496 ELSE
497 nb = 32
498 END IF
499 END IF
500 ELSE IF( sname .AND. c2.EQ.'ST' ) THEN
501 IF( c3.EQ.'EBZ' ) THEN
502 nb = 1
503 END IF
504 ELSE IF( c2.EQ.'GG' ) THEN
505 nb = 32
506 IF( c3.EQ.'HD3' ) THEN
507 IF( sname ) THEN
508 nb = 32
509 ELSE
510 nb = 32
511 END IF
512 END IF
513 END IF
514 ilaenv = nb
515 RETURN
516*
517 60 CONTINUE
518*
519* ISPEC = 2: minimum block size
520*
521 nbmin = 2
522 IF( c2.EQ.'GE' ) THEN
523 IF( c3.EQ.'QRF' .OR. c3.EQ.'RQF' .OR. c3.EQ.'LQF' .OR. c3.EQ.
524 $ 'QLF' ) THEN
525 IF( sname ) THEN
526 nbmin = 2
527 ELSE
528 nbmin = 2
529 END IF
530 ELSE IF( c3.EQ.'HRD' ) THEN
531 IF( sname ) THEN
532 nbmin = 2
533 ELSE
534 nbmin = 2
535 END IF
536 ELSE IF( c3.EQ.'BRD' ) THEN
537 IF( sname ) THEN
538 nbmin = 2
539 ELSE
540 nbmin = 2
541 END IF
542 ELSE IF( c3.EQ.'TRI' ) THEN
543 IF( sname ) THEN
544 nbmin = 2
545 ELSE
546 nbmin = 2
547 END IF
548 ELSE IF( subnam( 4: 7 ).EQ.'QP3RK' ) THEN
549 IF( sname ) THEN
550 nbmin = 2
551 ELSE
552 nbmin = 2
553 END IF
554 END IF
555
556 ELSE IF( c2.EQ.'SY' ) THEN
557 IF( c3.EQ.'TRF' ) THEN
558 IF( sname ) THEN
559 nbmin = 8
560 ELSE
561 nbmin = 8
562 END IF
563 ELSE IF( sname .AND. c3.EQ.'TRD' ) THEN
564 nbmin = 2
565 END IF
566 ELSE IF( cname .AND. c2.EQ.'HE' ) THEN
567 IF( c3.EQ.'TRD' ) THEN
568 nbmin = 2
569 END IF
570 ELSE IF( sname .AND. c2.EQ.'OR' ) THEN
571 IF( c3( 1: 1 ).EQ.'G' ) THEN
572 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
573 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
574 $ THEN
575 nbmin = 2
576 END IF
577 ELSE IF( c3( 1: 1 ).EQ.'M' ) THEN
578 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
579 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
580 $ THEN
581 nbmin = 2
582 END IF
583 END IF
584 ELSE IF( cname .AND. c2.EQ.'UN' ) THEN
585 IF( c3( 1: 1 ).EQ.'G' ) THEN
586 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
587 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
588 $ THEN
589 nbmin = 2
590 END IF
591 ELSE IF( c3( 1: 1 ).EQ.'M' ) THEN
592 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
593 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
594 $ THEN
595 nbmin = 2
596 END IF
597 END IF
598 ELSE IF( c2.EQ.'GG' ) THEN
599 nbmin = 2
600 IF( c3.EQ.'HD3' ) THEN
601 nbmin = 2
602 END IF
603 END IF
604 ilaenv = nbmin
605 RETURN
606*
607 70 CONTINUE
608*
609* ISPEC = 3: crossover point
610*
611 nx = 0
612 IF( c2.EQ.'GE' ) THEN
613 IF( c3.EQ.'QRF' .OR. c3.EQ.'RQF' .OR. c3.EQ.'LQF' .OR. c3.EQ.
614 $ 'QLF' ) THEN
615 IF( sname ) THEN
616 nx = 128
617 ELSE
618 nx = 128
619 END IF
620 ELSE IF( c3.EQ.'HRD' ) THEN
621 IF( sname ) THEN
622 nx = 128
623 ELSE
624 nx = 128
625 END IF
626 ELSE IF( c3.EQ.'BRD' ) THEN
627 IF( sname ) THEN
628 nx = 128
629 ELSE
630 nx = 128
631 END IF
632 ELSE IF( subnam( 4: 7 ).EQ.'QP3RK' ) THEN
633 IF( sname ) THEN
634 nx = 128
635 ELSE
636 nx = 128
637 END IF
638 END IF
639 ELSE IF( c2.EQ.'SY' ) THEN
640 IF( sname .AND. c3.EQ.'TRD' ) THEN
641 nx = 32
642 END IF
643 ELSE IF( cname .AND. c2.EQ.'HE' ) THEN
644 IF( c3.EQ.'TRD' ) THEN
645 nx = 32
646 END IF
647 ELSE IF( sname .AND. c2.EQ.'OR' ) THEN
648 IF( c3( 1: 1 ).EQ.'G' ) THEN
649 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
650 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
651 $ THEN
652 nx = 128
653 END IF
654 END IF
655 ELSE IF( cname .AND. c2.EQ.'UN' ) THEN
656 IF( c3( 1: 1 ).EQ.'G' ) THEN
657 IF( c4.EQ.'QR' .OR. c4.EQ.'RQ' .OR. c4.EQ.'LQ' .OR. c4.EQ.
658 $ 'QL' .OR. c4.EQ.'HR' .OR. c4.EQ.'TR' .OR. c4.EQ.'BR' )
659 $ THEN
660 nx = 128
661 END IF
662 END IF
663 ELSE IF( c2.EQ.'GG' ) THEN
664 nx = 128
665 IF( c3.EQ.'HD3' ) THEN
666 nx = 128
667 END IF
668 END IF
669 ilaenv = nx
670 RETURN
671*
672 80 CONTINUE
673*
674* ISPEC = 4: number of shifts (used by xHSEQR)
675*
676 ilaenv = 6
677 RETURN
678*
679 90 CONTINUE
680*
681* ISPEC = 5: minimum column dimension (not used)
682*
683 ilaenv = 2
684 RETURN
685*
686 100 CONTINUE
687*
688* ISPEC = 6: crossover point for SVD (used by xGELSS and xGESVD)
689*
690 ilaenv = int( real( min( n1, n2 ) )*1.6e0 )
691 RETURN
692*
693 110 CONTINUE
694*
695* ISPEC = 7: number of processors (not used)
696*
697 ilaenv = 1
698 RETURN
699*
700 120 CONTINUE
701*
702* ISPEC = 8: crossover point for multishift (used by xHSEQR)
703*
704 ilaenv = 50
705 RETURN
706*
707 130 CONTINUE
708*
709* ISPEC = 9: maximum size of the subproblems at the bottom of the
710* computation tree in the divide-and-conquer algorithm
711* (used by xGELSD and xGESDD)
712*
713 ilaenv = 25
714 RETURN
715*
716 140 CONTINUE
717*
718* ISPEC = 10: ieee and infinity NaN arithmetic can be trusted not to trap
719*
720* ILAENV = 0
721 ilaenv = 1
722 IF( ilaenv.EQ.1 ) THEN
723 ilaenv = ieeeck( 1, 0.0, 1.0 )
724 END IF
725 RETURN
726*
727 150 CONTINUE
728*
729* ISPEC = 11: ieee infinity arithmetic can be trusted not to trap
730*
731* ILAENV = 0
732 ilaenv = 1
733 IF( ilaenv.EQ.1 ) THEN
734 ilaenv = ieeeck( 0, 0.0, 1.0 )
735 END IF
736 RETURN
737*
738 160 CONTINUE
739*
740* 12 <= ISPEC <= 17: xHSEQR or related subroutines.
741*
742 ilaenv = iparmq( ispec, name, opts, n1, n2, n3, n4 )
743 RETURN
744*
745* End of ILAENV
746*
747 END
ieeeck
integer function ieeeck(ispec, zero, one)
IEEECK
Definition ieeeck.f:80
ilaenv
integer function ilaenv(ispec, name, opts, n1, n2, n3, n4)
ILAENV
Definition ilaenv.f:160
iparam2stage
integer function iparam2stage(ispec, name, opts, ni, nbi, ibi, nxi)
IPARAM2STAGE
Definition iparam2stage.F:153
iparmq
integer function iparmq(ispec, name, opts, n, ilo, ihi, lwork)
IPARMQ
Definition iparmq.f:229