LAPACK 3.12.0 LAPACK: Linear Algebra PACKage
Searching...
No Matches

## ◆ dsytrf_aa_2stage()

 subroutine dsytrf_aa_2stage ( character uplo, integer n, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( * ) tb, integer ltb, integer, dimension( * ) ipiv, integer, dimension( * ) ipiv2, double precision, dimension( * ) work, integer lwork, integer info )

DSYTRF_AA_2STAGE

Purpose:
``` DSYTRF_AA_2STAGE computes the factorization of a real symmetric matrix A
using the Aasen's algorithm.  The form of the factorization is

A = U**T*T*U  or  A = L*T*L**T

where U (or L) is a product of permutation and unit upper (lower)
triangular matrices, and T is a symmetric band matrix with the
bandwidth of NB (NB is internally selected and stored in TB( 1 ), and T is
LU factorized with partial pivoting).

This is the blocked version of the algorithm, calling Level 3 BLAS.```
Parameters
 [in] UPLO ``` UPLO is CHARACTER*1 = 'U': Upper triangle of A is stored; = 'L': Lower triangle of A is stored.``` [in] N ``` N is INTEGER The order of the matrix A. N >= 0.``` [in,out] A ``` A is DOUBLE PRECISION array, dimension (LDA,N) On entry, the symmetric matrix A. If UPLO = 'U', the leading N-by-N upper triangular part of A contains the upper triangular part of the matrix A, and the strictly lower triangular part of A is not referenced. If UPLO = 'L', the leading N-by-N lower triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part of A is not referenced. On exit, L is stored below (or above) the subdiagonal blocks, when UPLO is 'L' (or 'U').``` [in] LDA ``` LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N).``` [out] TB ``` TB is DOUBLE PRECISION array, dimension (LTB) On exit, details of the LU factorization of the band matrix.``` [in] LTB ``` LTB is INTEGER The size of the array TB. LTB >= 4*N, internally used to select NB such that LTB >= (3*NB+1)*N. If LTB = -1, then a workspace query is assumed; the routine only calculates the optimal size of LTB, returns this value as the first entry of TB, and no error message related to LTB is issued by XERBLA.``` [out] IPIV ``` IPIV is INTEGER array, dimension (N) On exit, it contains the details of the interchanges, i.e., the row and column k of A were interchanged with the row and column IPIV(k).``` [out] IPIV2 ``` IPIV2 is INTEGER array, dimension (N) On exit, it contains the details of the interchanges, i.e., the row and column k of T were interchanged with the row and column IPIV2(k).``` [out] WORK ` WORK is DOUBLE PRECISION workspace of size LWORK` [in] LWORK ``` LWORK is INTEGER The size of WORK. LWORK >= N, internally used to select NB such that LWORK >= N*NB. If LWORK = -1, then a workspace query is assumed; the routine only calculates the optimal size of the WORK array, returns this value as the first entry of the WORK array, and no error message related to LWORK is issued by XERBLA.``` [out] INFO ``` INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument had an illegal value. > 0: if INFO = i, band LU factorization failed on i-th column```

Definition at line 158 of file dsytrf_aa_2stage.f.

160*
161* -- LAPACK computational 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 IMPLICIT NONE
166*
167* .. Scalar Arguments ..
168 CHARACTER UPLO
169 INTEGER N, LDA, LTB, LWORK, INFO
170* ..
171* .. Array Arguments ..
172 INTEGER IPIV( * ), IPIV2( * )
173 DOUBLE PRECISION A( LDA, * ), TB( * ), WORK( * )
174* ..
175*
176* =====================================================================
177* .. Parameters ..
178 DOUBLE PRECISION ZERO, ONE
179 parameter( zero = 0.0d+0, one = 1.0d+0 )
180*
181* .. Local Scalars ..
182 LOGICAL UPPER, TQUERY, WQUERY
183 INTEGER I, J, K, I1, I2, TD
184 INTEGER LDTB, NB, KB, JB, NT, IINFO
185 DOUBLE PRECISION PIV
186* ..
187* .. External Functions ..
188 LOGICAL LSAME
189 INTEGER ILAENV
190 EXTERNAL lsame, ilaenv
191* ..
192* .. External Subroutines ..
193 EXTERNAL xerbla, dcopy, dlacpy,
195 \$ dsygst, dswap, dtrsm
196* ..
197* .. Intrinsic Functions ..
198 INTRINSIC min, max
199* ..
200* .. Executable Statements ..
201*
202* Test the input parameters.
203*
204 info = 0
205 upper = lsame( uplo, 'U' )
206 wquery = ( lwork.EQ.-1 )
207 tquery = ( ltb.EQ.-1 )
208 IF( .NOT.upper .AND. .NOT.lsame( uplo, 'L' ) ) THEN
209 info = -1
210 ELSE IF( n.LT.0 ) THEN
211 info = -2
212 ELSE IF( lda.LT.max( 1, n ) ) THEN
213 info = -4
214 ELSE IF ( ltb .LT. 4*n .AND. .NOT.tquery ) THEN
215 info = -6
216 ELSE IF ( lwork .LT. n .AND. .NOT.wquery ) THEN
217 info = -10
218 END IF
219*
220 IF( info.NE.0 ) THEN
221 CALL xerbla( 'DSYTRF_AA_2STAGE', -info )
222 RETURN
223 END IF
224*
226*
227 nb = ilaenv( 1, 'DSYTRF_AA_2STAGE', uplo, n, -1, -1, -1 )
228 IF( info.EQ.0 ) THEN
229 IF( tquery ) THEN
230 tb( 1 ) = (3*nb+1)*n
231 END IF
232 IF( wquery ) THEN
233 work( 1 ) = n*nb
234 END IF
235 END IF
236 IF( tquery .OR. wquery ) THEN
237 RETURN
238 END IF
239*
240* Quick return
241*
242 IF ( n.EQ.0 ) THEN
243 RETURN
244 ENDIF
245*
246* Determine the number of the block size
247*
248 ldtb = ltb/n
249 IF( ldtb .LT. 3*nb+1 ) THEN
250 nb = (ldtb-1)/3
251 END IF
252 IF( lwork .LT. nb*n ) THEN
253 nb = lwork/n
254 END IF
255*
256* Determine the number of the block columns
257*
258 nt = (n+nb-1)/nb
259 td = 2*nb
260 kb = min(nb, n)
261*
262* Initialize vectors/matrices
263*
264 DO j = 1, kb
265 ipiv( j ) = j
266 END DO
267*
268* Save NB
269*
270 tb( 1 ) = nb
271*
272 IF( upper ) THEN
273*
274* .....................................................
275* Factorize A as U**T*D*U using the upper triangle of A
276* .....................................................
277*
278 DO j = 0, nt-1
279*
280* Generate Jth column of W and H
281*
282 kb = min(nb, n-j*nb)
283 DO i = 1, j-1
284 IF( i .EQ. 1 ) THEN
285* H(I,J) = T(I,I)*U(I,J) + T(I,I+1)*U(I+1,J)
286 IF( i .EQ. (j-1) ) THEN
287 jb = nb+kb
288 ELSE
289 jb = 2*nb
290 END IF
291 CALL dgemm( 'NoTranspose', 'NoTranspose',
292 \$ nb, kb, jb,
293 \$ one, tb( td+1 + (i*nb)*ldtb ), ldtb-1,
294 \$ a( (i-1)*nb+1, j*nb+1 ), lda,
295 \$ zero, work( i*nb+1 ), n )
296 ELSE
297* H(I,J) = T(I,I-1)*U(I-1,J) + T(I,I)*U(I,J) + T(I,I+1)*U(I+1,J)
298 IF( i .EQ. j-1) THEN
299 jb = 2*nb+kb
300 ELSE
301 jb = 3*nb
302 END IF
303 CALL dgemm( 'NoTranspose', 'NoTranspose',
304 \$ nb, kb, jb,
305 \$ one, tb( td+nb+1 + ((i-1)*nb)*ldtb ),
306 \$ ldtb-1,
307 \$ a( (i-2)*nb+1, j*nb+1 ), lda,
308 \$ zero, work( i*nb+1 ), n )
309 END IF
310 END DO
311*
312* Compute T(J,J)
313*
314 CALL dlacpy( 'Upper', kb, kb, a( j*nb+1, j*nb+1 ), lda,
315 \$ tb( td+1 + (j*nb)*ldtb ), ldtb-1 )
316 IF( j.GT.1 ) THEN
317* T(J,J) = U(1:J,J)'*H(1:J)
318 CALL dgemm( 'Transpose', 'NoTranspose',
319 \$ kb, kb, (j-1)*nb,
320 \$ -one, a( 1, j*nb+1 ), lda,
321 \$ work( nb+1 ), n,
322 \$ one, tb( td+1 + (j*nb)*ldtb ), ldtb-1 )
323* T(J,J) += U(J,J)'*T(J,J-1)*U(J-1,J)
324 CALL dgemm( 'Transpose', 'NoTranspose',
325 \$ kb, nb, kb,
326 \$ one, a( (j-1)*nb+1, j*nb+1 ), lda,
327 \$ tb( td+nb+1 + ((j-1)*nb)*ldtb ), ldtb-1,
328 \$ zero, work( 1 ), n )
329 CALL dgemm( 'NoTranspose', 'NoTranspose',
330 \$ kb, kb, nb,
331 \$ -one, work( 1 ), n,
332 \$ a( (j-2)*nb+1, j*nb+1 ), lda,
333 \$ one, tb( td+1 + (j*nb)*ldtb ), ldtb-1 )
334 END IF
335 IF( j.GT.0 ) THEN
336 CALL dsygst( 1, 'Upper', kb,
337 \$ tb( td+1 + (j*nb)*ldtb ), ldtb-1,
338 \$ a( (j-1)*nb+1, j*nb+1 ), lda, iinfo )
339 END IF
340*
341* Expand T(J,J) into full format
342*
343 DO i = 1, kb
344 DO k = i+1, kb
345 tb( td+(k-i)+1 + (j*nb+i-1)*ldtb )
346 \$ = tb( td-(k-(i+1)) + (j*nb+k-1)*ldtb )
347 END DO
348 END DO
349*
350 IF( j.LT.nt-1 ) THEN
351 IF( j.GT.0 ) THEN
352*
353* Compute H(J,J)
354*
355 IF( j.EQ.1 ) THEN
356 CALL dgemm( 'NoTranspose', 'NoTranspose',
357 \$ kb, kb, kb,
358 \$ one, tb( td+1 + (j*nb)*ldtb ), ldtb-1,
359 \$ a( (j-1)*nb+1, j*nb+1 ), lda,
360 \$ zero, work( j*nb+1 ), n )
361 ELSE
362 CALL dgemm( 'NoTranspose', 'NoTranspose',
363 \$ kb, kb, nb+kb,
364 \$ one, tb( td+nb+1 + ((j-1)*nb)*ldtb ),
365 \$ ldtb-1,
366 \$ a( (j-2)*nb+1, j*nb+1 ), lda,
367 \$ zero, work( j*nb+1 ), n )
368 END IF
369*
370* Update with the previous column
371*
372 CALL dgemm( 'Transpose', 'NoTranspose',
373 \$ nb, n-(j+1)*nb, j*nb,
374 \$ -one, work( nb+1 ), n,
375 \$ a( 1, (j+1)*nb+1 ), lda,
376 \$ one, a( j*nb+1, (j+1)*nb+1 ), lda )
377 END IF
378*
379* Copy panel to workspace to call DGETRF
380*
381 DO k = 1, nb
382 CALL dcopy( n-(j+1)*nb,
383 \$ a( j*nb+k, (j+1)*nb+1 ), lda,
384 \$ work( 1+(k-1)*n ), 1 )
385 END DO
386*
387* Factorize panel
388*
389 CALL dgetrf( n-(j+1)*nb, nb,
390 \$ work, n,
391 \$ ipiv( (j+1)*nb+1 ), iinfo )
392c IF (IINFO.NE.0 .AND. INFO.EQ.0) THEN
393c INFO = IINFO+(J+1)*NB
394c END IF
395*
396* Copy panel back
397*
398 DO k = 1, nb
399 CALL dcopy( n-(j+1)*nb,
400 \$ work( 1+(k-1)*n ), 1,
401 \$ a( j*nb+k, (j+1)*nb+1 ), lda )
402 END DO
403*
404* Compute T(J+1, J), zero out for GEMM update
405*
406 kb = min(nb, n-(j+1)*nb)
407 CALL dlaset( 'Full', kb, nb, zero, zero,
408 \$ tb( td+nb+1 + (j*nb)*ldtb), ldtb-1 )
409 CALL dlacpy( 'Upper', kb, nb,
410 \$ work, n,
411 \$ tb( td+nb+1 + (j*nb)*ldtb ), ldtb-1 )
412 IF( j.GT.0 ) THEN
413 CALL dtrsm( 'R', 'U', 'N', 'U', kb, nb, one,
414 \$ a( (j-1)*nb+1, j*nb+1 ), lda,
415 \$ tb( td+nb+1 + (j*nb)*ldtb ), ldtb-1 )
416 END IF
417*
418* Copy T(J,J+1) into T(J+1, J), both upper/lower for GEMM
420*
421 DO k = 1, nb
422 DO i = 1, kb
423 tb( td-nb+k-i+1 + (j*nb+nb+i-1)*ldtb )
424 \$ = tb( td+nb+i-k+1 + (j*nb+k-1)*ldtb )
425 END DO
426 END DO
427 CALL dlaset( 'Lower', kb, nb, zero, one,
428 \$ a( j*nb+1, (j+1)*nb+1), lda )
429*
430* Apply pivots to trailing submatrix of A
431*
432 DO k = 1, kb
434 ipiv( (j+1)*nb+k ) = ipiv( (j+1)*nb+k ) + (j+1)*nb
435*
436 i1 = (j+1)*nb+k
437 i2 = ipiv( (j+1)*nb+k )
438 IF( i1.NE.i2 ) THEN
439* > Apply pivots to previous columns of L
440 CALL dswap( k-1, a( (j+1)*nb+1, i1 ), 1,
441 \$ a( (j+1)*nb+1, i2 ), 1 )
442* > Swap A(I1+1:M, I1) with A(I2, I1+1:M)
443 IF( i2.GT.(i1+1) )
444 \$ CALL dswap( i2-i1-1, a( i1, i1+1 ), lda,
445 \$ a( i1+1, i2 ), 1 )
446* > Swap A(I2+1:M, I1) with A(I2+1:M, I2)
447 IF( i2.LT.n )
448 \$ CALL dswap( n-i2, a( i1, i2+1 ), lda,
449 \$ a( i2, i2+1 ), lda )
450* > Swap A(I1, I1) with A(I2, I2)
451 piv = a( i1, i1 )
452 a( i1, i1 ) = a( i2, i2 )
453 a( i2, i2 ) = piv
454* > Apply pivots to previous columns of L
455 IF( j.GT.0 ) THEN
456 CALL dswap( j*nb, a( 1, i1 ), 1,
457 \$ a( 1, i2 ), 1 )
458 END IF
459 ENDIF
460 END DO
461 END IF
462 END DO
463 ELSE
464*
465* .....................................................
466* Factorize A as L*D*L**T using the lower triangle of A
467* .....................................................
468*
469 DO j = 0, nt-1
470*
471* Generate Jth column of W and H
472*
473 kb = min(nb, n-j*nb)
474 DO i = 1, j-1
475 IF( i.EQ.1 ) THEN
476* H(I,J) = T(I,I)*L(J,I)' + T(I+1,I)'*L(J,I+1)'
477 IF( i .EQ. j-1) THEN
478 jb = nb+kb
479 ELSE
480 jb = 2*nb
481 END IF
482 CALL dgemm( 'NoTranspose', 'Transpose',
483 \$ nb, kb, jb,
484 \$ one, tb( td+1 + (i*nb)*ldtb ), ldtb-1,
485 \$ a( j*nb+1, (i-1)*nb+1 ), lda,
486 \$ zero, work( i*nb+1 ), n )
487 ELSE
488* H(I,J) = T(I,I-1)*L(J,I-1)' + T(I,I)*L(J,I)' + T(I,I+1)*L(J,I+1)'
489 IF( i .EQ. j-1) THEN
490 jb = 2*nb+kb
491 ELSE
492 jb = 3*nb
493 END IF
494 CALL dgemm( 'NoTranspose', 'Transpose',
495 \$ nb, kb, jb,
496 \$ one, tb( td+nb+1 + ((i-1)*nb)*ldtb ),
497 \$ ldtb-1,
498 \$ a( j*nb+1, (i-2)*nb+1 ), lda,
499 \$ zero, work( i*nb+1 ), n )
500 END IF
501 END DO
502*
503* Compute T(J,J)
504*
505 CALL dlacpy( 'Lower', kb, kb, a( j*nb+1, j*nb+1 ), lda,
506 \$ tb( td+1 + (j*nb)*ldtb ), ldtb-1 )
507 IF( j.GT.1 ) THEN
508* T(J,J) = L(J,1:J)*H(1:J)
509 CALL dgemm( 'NoTranspose', 'NoTranspose',
510 \$ kb, kb, (j-1)*nb,
511 \$ -one, a( j*nb+1, 1 ), lda,
512 \$ work( nb+1 ), n,
513 \$ one, tb( td+1 + (j*nb)*ldtb ), ldtb-1 )
514* T(J,J) += L(J,J)*T(J,J-1)*L(J,J-1)'
515 CALL dgemm( 'NoTranspose', 'NoTranspose',
516 \$ kb, nb, kb,
517 \$ one, a( j*nb+1, (j-1)*nb+1 ), lda,
518 \$ tb( td+nb+1 + ((j-1)*nb)*ldtb ), ldtb-1,
519 \$ zero, work( 1 ), n )
520 CALL dgemm( 'NoTranspose', 'Transpose',
521 \$ kb, kb, nb,
522 \$ -one, work( 1 ), n,
523 \$ a( j*nb+1, (j-2)*nb+1 ), lda,
524 \$ one, tb( td+1 + (j*nb)*ldtb ), ldtb-1 )
525 END IF
526 IF( j.GT.0 ) THEN
527 CALL dsygst( 1, 'Lower', kb,
528 \$ tb( td+1 + (j*nb)*ldtb ), ldtb-1,
529 \$ a( j*nb+1, (j-1)*nb+1 ), lda, iinfo )
530 END IF
531*
532* Expand T(J,J) into full format
533*
534 DO i = 1, kb
535 DO k = i+1, kb
536 tb( td-(k-(i+1)) + (j*nb+k-1)*ldtb )
537 \$ = tb( td+(k-i)+1 + (j*nb+i-1)*ldtb )
538 END DO
539 END DO
540*
541 IF( j.LT.nt-1 ) THEN
542 IF( j.GT.0 ) THEN
543*
544* Compute H(J,J)
545*
546 IF( j.EQ.1 ) THEN
547 CALL dgemm( 'NoTranspose', 'Transpose',
548 \$ kb, kb, kb,
549 \$ one, tb( td+1 + (j*nb)*ldtb ), ldtb-1,
550 \$ a( j*nb+1, (j-1)*nb+1 ), lda,
551 \$ zero, work( j*nb+1 ), n )
552 ELSE
553 CALL dgemm( 'NoTranspose', 'Transpose',
554 \$ kb, kb, nb+kb,
555 \$ one, tb( td+nb+1 + ((j-1)*nb)*ldtb ),
556 \$ ldtb-1,
557 \$ a( j*nb+1, (j-2)*nb+1 ), lda,
558 \$ zero, work( j*nb+1 ), n )
559 END IF
560*
561* Update with the previous column
562*
563 CALL dgemm( 'NoTranspose', 'NoTranspose',
564 \$ n-(j+1)*nb, nb, j*nb,
565 \$ -one, a( (j+1)*nb+1, 1 ), lda,
566 \$ work( nb+1 ), n,
567 \$ one, a( (j+1)*nb+1, j*nb+1 ), lda )
568 END IF
569*
570* Factorize panel
571*
572 CALL dgetrf( n-(j+1)*nb, nb,
573 \$ a( (j+1)*nb+1, j*nb+1 ), lda,
574 \$ ipiv( (j+1)*nb+1 ), iinfo )
575c IF (IINFO.NE.0 .AND. INFO.EQ.0) THEN
576c INFO = IINFO+(J+1)*NB
577c END IF
578*
579* Compute T(J+1, J), zero out for GEMM update
580*
581 kb = min(nb, n-(j+1)*nb)
582 CALL dlaset( 'Full', kb, nb, zero, zero,
583 \$ tb( td+nb+1 + (j*nb)*ldtb), ldtb-1 )
584 CALL dlacpy( 'Upper', kb, nb,
585 \$ a( (j+1)*nb+1, j*nb+1 ), lda,
586 \$ tb( td+nb+1 + (j*nb)*ldtb ), ldtb-1 )
587 IF( j.GT.0 ) THEN
588 CALL dtrsm( 'R', 'L', 'T', 'U', kb, nb, one,
589 \$ a( j*nb+1, (j-1)*nb+1 ), lda,
590 \$ tb( td+nb+1 + (j*nb)*ldtb ), ldtb-1 )
591 END IF
592*
593* Copy T(J+1,J) into T(J, J+1), both upper/lower for GEMM
595*
596 DO k = 1, nb
597 DO i = 1, kb
598 tb( td-nb+k-i+1 + (j*nb+nb+i-1)*ldtb )
599 \$ = tb( td+nb+i-k+1 + (j*nb+k-1)*ldtb )
600 END DO
601 END DO
602 CALL dlaset( 'Upper', kb, nb, zero, one,
603 \$ a( (j+1)*nb+1, j*nb+1), lda )
604*
605* Apply pivots to trailing submatrix of A
606*
607 DO k = 1, kb
609 ipiv( (j+1)*nb+k ) = ipiv( (j+1)*nb+k ) + (j+1)*nb
610*
611 i1 = (j+1)*nb+k
612 i2 = ipiv( (j+1)*nb+k )
613 IF( i1.NE.i2 ) THEN
614* > Apply pivots to previous columns of L
615 CALL dswap( k-1, a( i1, (j+1)*nb+1 ), lda,
616 \$ a( i2, (j+1)*nb+1 ), lda )
617* > Swap A(I1+1:M, I1) with A(I2, I1+1:M)
618 IF( i2.GT.(i1+1) )
619 \$ CALL dswap( i2-i1-1, a( i1+1, i1 ), 1,
620 \$ a( i2, i1+1 ), lda )
621* > Swap A(I2+1:M, I1) with A(I2+1:M, I2)
622 IF( i2.LT.n )
623 \$ CALL dswap( n-i2, a( i2+1, i1 ), 1,
624 \$ a( i2+1, i2 ), 1 )
625* > Swap A(I1, I1) with A(I2, I2)
626 piv = a( i1, i1 )
627 a( i1, i1 ) = a( i2, i2 )
628 a( i2, i2 ) = piv
629* > Apply pivots to previous columns of L
630 IF( j.GT.0 ) THEN
631 CALL dswap( j*nb, a( i1, 1 ), lda,
632 \$ a( i2, 1 ), lda )
633 END IF
634 ENDIF
635 END DO
636*
637* Apply pivots to previous columns of L
638*
639c CALL DLASWP( J*NB, A( 1, 1 ), LDA,
640c \$ (J+1)*NB+1, (J+1)*NB+KB, IPIV, 1 )
641 END IF
642 END DO
643 END IF
644*
645* Factor the band matrix
646 CALL dgbtrf( n, n, nb, nb, tb, ldtb, ipiv2, info )
647*
648 RETURN
649*
650* End of DSYTRF_AA_2STAGE
651*
subroutine xerbla(srname, info)
Definition cblat2.f:3285
subroutine dcopy(n, dx, incx, dy, incy)
DCOPY
Definition dcopy.f:82
subroutine dgbtrf(m, n, kl, ku, ab, ldab, ipiv, info)
DGBTRF
Definition dgbtrf.f:144
subroutine dgemm(transa, transb, m, n, k, alpha, a, lda, b, ldb, beta, c, ldc)
DGEMM
Definition dgemm.f:188
subroutine dgetrf(m, n, a, lda, ipiv, info)
DGETRF
Definition dgetrf.f:108
subroutine dsygst(itype, uplo, n, a, lda, b, ldb, info)
DSYGST
Definition dsygst.f:127
integer function ilaenv(ispec, name, opts, n1, n2, n3, n4)
ILAENV
Definition ilaenv.f:162
subroutine dlacpy(uplo, m, n, a, lda, b, ldb)
DLACPY copies all or part of one two-dimensional array to another.
Definition dlacpy.f:103
subroutine dlaset(uplo, m, n, alpha, beta, a, lda)
DLASET initializes the off-diagonal elements and the diagonal elements of a matrix to given values.
Definition dlaset.f:110
logical function lsame(ca, cb)
LSAME
Definition lsame.f:48
subroutine dswap(n, dx, incx, dy, incy)
DSWAP
Definition dswap.f:82
subroutine dtrsm(side, uplo, transa, diag, m, n, alpha, a, lda, b, ldb)
DTRSM
Definition dtrsm.f:181
Here is the call graph for this function:
Here is the caller graph for this function: