6
c Reverse communication interface for the Implicitly Restarted Arnoldi
7
c iteration. This subroutine computes approximations to a few eigenpairs
8
c of a linear operator "OP" with respect to a semi-inner product defined by
9
c a symmetric positive semi-definite real matrix B. B may be the identity
10
c matrix. NOTE: If the linear operator "OP" is real and symmetric
11
c with respect to the real positive semi-definite symmetric matrix B,
12
c i.e. B*OP = (OP`)*B, then subroutine ssaupd should be used instead.
14
c The computed approximate eigenvalues are called Ritz values and
15
c the corresponding approximate eigenvectors are called Ritz vectors.
17
c snaupd is usually called iteratively to solve one of the
20
c Mode 1: A*x = lambda*x.
21
c ===> OP = A and B = I.
23
c Mode 2: A*x = lambda*M*x, M symmetric positive definite
24
c ===> OP = inv[M]*A and B = M.
25
c ===> (If M can be factored see remark 3 below)
27
c Mode 3: A*x = lambda*M*x, M symmetric semi-definite
28
c ===> OP = Real_Part{ inv[A - sigma*M]*M } and B = M.
29
c ===> shift-and-invert mode (in real arithmetic)
30
c If OP*x = amu*x, then
31
c amu = 1/2 * [ 1/(lambda-sigma) + 1/(lambda-conjg(sigma)) ].
32
c Note: If sigma is real, i.e. imaginary part of sigma is zero;
33
c Real_Part{ inv[A - sigma*M]*M } == inv[A - sigma*M]*M
34
c amu == 1/(lambda-sigma).
36
c Mode 4: A*x = lambda*M*x, M symmetric semi-definite
37
c ===> OP = Imaginary_Part{ inv[A - sigma*M]*M } and B = M.
38
c ===> shift-and-invert mode (in real arithmetic)
39
c If OP*x = amu*x, then
40
c amu = 1/2i * [ 1/(lambda-sigma) - 1/(lambda-conjg(sigma)) ].
42
c Both mode 3 and 4 give the same enhancement to eigenvalues close to
43
c the (complex) shift sigma. However, as lambda goes to infinity,
44
c the operator OP in mode 4 dampens the eigenvalues more strongly than
45
c does OP defined in mode 3.
47
c NOTE: The action of w <- inv[A - sigma*M]*v or w <- inv[M]*v
48
c should be accomplished either by a direct method
49
c using a sparse matrix factorization and solving
51
c [A - sigma*M]*w = v or M*w = v,
53
c or through an iterative method for solving these
54
c systems. If an iterative method is used, the
55
c convergence test must be more stringent than
56
c the accuracy requirements for the eigenvalue
61
c ( IDO, BMAT, N, WHICH, NEV, TOL, RESID, NCV, V, LDV, IPARAM,
62
c IPNTR, WORKD, WORKL, LWORKL, INFO )
65
c IDO Integer. (INPUT/OUTPUT)
66
c Reverse communication flag. IDO must be zero on the first
67
c call to snaupd. IDO will be set internally to
68
c indicate the type of operation to be performed. Control is
69
c then given back to the calling routine which has the
70
c responsibility to carry out the requested operation and call
71
c snaupd with the result. The operand is given in
72
c WORKD(IPNTR(1)), the result must be put in WORKD(IPNTR(2)).
73
c -------------------------------------------------------------
74
c IDO = 0: first call to the reverse communication interface
75
c IDO = -1: compute Y = OP * X where
76
c IPNTR(1) is the pointer into WORKD for X,
77
c IPNTR(2) is the pointer into WORKD for Y.
78
c This is for the initialization phase to force the
79
c starting vector into the range of OP.
80
c IDO = 1: compute Y = OP * X where
81
c IPNTR(1) is the pointer into WORKD for X,
82
c IPNTR(2) is the pointer into WORKD for Y.
83
c In mode 3 and 4, the vector B * X is already
84
c available in WORKD(ipntr(3)). It does not
85
c need to be recomputed in forming OP * X.
86
c IDO = 2: compute Y = B * X where
87
c IPNTR(1) is the pointer into WORKD for X,
88
c IPNTR(2) is the pointer into WORKD for Y.
89
c IDO = 3: compute the IPARAM(8) real and imaginary parts
90
c of the shifts where INPTR(14) is the pointer
91
c into WORKL for placing the shifts. See Remark
94
c -------------------------------------------------------------
96
c BMAT Character*1. (INPUT)
97
c BMAT specifies the type of the matrix B that defines the
98
c semi-inner product for the operator OP.
99
c BMAT = 'I' -> standard eigenvalue problem A*x = lambda*x
100
c BMAT = 'G' -> generalized eigenvalue problem A*x = lambda*B*x
103
c Dimension of the eigenproblem.
105
c WHICH Character*2. (INPUT)
106
c 'LM' -> want the NEV eigenvalues of largest magnitude.
107
c 'SM' -> want the NEV eigenvalues of smallest magnitude.
108
c 'LR' -> want the NEV eigenvalues of largest real part.
109
c 'SR' -> want the NEV eigenvalues of smallest real part.
110
c 'LI' -> want the NEV eigenvalues of largest imaginary part.
111
c 'SI' -> want the NEV eigenvalues of smallest imaginary part.
113
c NEV Integer. (INPUT/OUTPUT)
114
c Number of eigenvalues of OP to be computed. 0 < NEV < N-1.
116
c TOL Real scalar. (INPUT)
117
c Stopping criterion: the relative accuracy of the Ritz value
118
c is considered acceptable if BOUNDS(I) .LE. TOL*ABS(RITZ(I))
119
c where ABS(RITZ(I)) is the magnitude when RITZ(I) is complex.
120
c DEFAULT = SLAMCH('EPS') (machine precision as computed
121
c by the LAPACK auxiliary subroutine SLAMCH).
123
c RESID Real array of length N. (INPUT/OUTPUT)
125
c If INFO .EQ. 0, a random initial residual vector is used.
126
c If INFO .NE. 0, RESID contains the initial residual vector,
127
c possibly from a previous run.
129
c RESID contains the final residual vector.
131
c NCV Integer. (INPUT)
132
c Number of columns of the matrix V. NCV must satisfy the two
133
c inequalities 2 <= NCV-NEV and NCV <= N.
134
c This will indicate how many Arnoldi vectors are generated
135
c at each iteration. After the startup phase in which NEV
136
c Arnoldi vectors are generated, the algorithm generates
137
c approximately NCV-NEV Arnoldi vectors at each subsequent update
138
c iteration. Most of the cost in generating each Arnoldi vector is
139
c in the matrix-vector operation OP*x.
140
c NOTE: 2 <= NCV-NEV in order that complex conjugate pairs of Ritz
141
c values are kept together. (See remark 4 below)
143
c V Real array N by NCV. (OUTPUT)
144
c Contains the final set of Arnoldi basis vectors.
146
c LDV Integer. (INPUT)
147
c Leading dimension of V exactly as declared in the calling program.
149
c IPARAM Integer array of length 11. (INPUT/OUTPUT)
150
c IPARAM(1) = ISHIFT: method for selecting the implicit shifts.
151
c The shifts selected at each iteration are used to restart
152
c the Arnoldi iteration in an implicit fashion.
153
c -------------------------------------------------------------
154
c ISHIFT = 0: the shifts are provided by the user via
155
c reverse communication. The real and imaginary
156
c parts of the NCV eigenvalues of the Hessenberg
157
c matrix H are returned in the part of the WORKL
158
c array corresponding to RITZR and RITZI. See remark
160
c ISHIFT = 1: exact shifts with respect to the current
161
c Hessenberg matrix H. This is equivalent to
162
c restarting the iteration with a starting vector
163
c that is a linear combination of approximate Schur
164
c vectors associated with the "wanted" Ritz values.
165
c -------------------------------------------------------------
167
c IPARAM(2) = No longer referenced.
170
c On INPUT: maximum number of Arnoldi update iterations allowed.
171
c On OUTPUT: actual number of Arnoldi update iterations taken.
173
c IPARAM(4) = NB: blocksize to be used in the recurrence.
174
c The code currently works only for NB = 1.
176
c IPARAM(5) = NCONV: number of "converged" Ritz values.
177
c This represents the number of Ritz values that satisfy
178
c the convergence criterion.
181
c No longer referenced. Implicit restarting is ALWAYS used.
184
c On INPUT determines what type of eigenproblem is being solved.
185
c Must be 1,2,3,4; See under \Description of snaupd for the
186
c four modes available.
189
c When ido = 3 and the user provides shifts through reverse
190
c communication (IPARAM(1)=0), snaupd returns NP, the number
191
c of shifts the user is to provide. 0 < NP <=NCV-NEV. See Remark
194
c IPARAM(9) = NUMOP, IPARAM(10) = NUMOPB, IPARAM(11) = NUMREO,
195
c OUTPUT: NUMOP = total number of OP*x operations,
196
c NUMOPB = total number of B*x operations if BMAT='G',
197
c NUMREO = total number of steps of re-orthogonalization.
199
c IPNTR Integer array of length 14. (OUTPUT)
200
c Pointer to mark the starting locations in the WORKD and WORKL
201
c arrays for matrices/vectors used by the Arnoldi iteration.
202
c -------------------------------------------------------------
203
c IPNTR(1): pointer to the current operand vector X in WORKD.
204
c IPNTR(2): pointer to the current result vector Y in WORKD.
205
c IPNTR(3): pointer to the vector B * X in WORKD when used in
206
c the shift-and-invert mode.
207
c IPNTR(4): pointer to the next available location in WORKL
208
c that is untouched by the program.
209
c IPNTR(5): pointer to the NCV by NCV upper Hessenberg matrix
211
c IPNTR(6): pointer to the real part of the ritz value array
213
c IPNTR(7): pointer to the imaginary part of the ritz value array
215
c IPNTR(8): pointer to the Ritz estimates in array WORKL associated
216
c with the Ritz values located in RITZR and RITZI in WORKL.
218
c IPNTR(14): pointer to the NP shifts in WORKL. See Remark 5 below.
220
c Note: IPNTR(9:13) is only referenced by sneupd. See Remark 2 below.
222
c IPNTR(9): pointer to the real part of the NCV RITZ values of the
224
c IPNTR(10): pointer to the imaginary part of the NCV RITZ values of
225
c the original system.
226
c IPNTR(11): pointer to the NCV corresponding error bounds.
227
c IPNTR(12): pointer to the NCV by NCV upper quasi-triangular
228
c Schur matrix for H.
229
c IPNTR(13): pointer to the NCV by NCV matrix of eigenvectors
230
c of the upper Hessenberg matrix H. Only referenced by
231
c sneupd if RVEC = .TRUE. See Remark 2 below.
232
c -------------------------------------------------------------
234
c WORKD Real work array of length 3*N. (REVERSE COMMUNICATION)
235
c Distributed array to be used in the basic Arnoldi iteration
236
c for reverse communication. The user should not use WORKD
237
c as temporary workspace during the iteration. Upon termination
238
c WORKD(1:N) contains B*RESID(1:N). If an invariant subspace
239
c associated with the converged Ritz values is desired, see remark
240
c 2 below, subroutine sneupd uses this output.
241
c See Data Distribution Note below.
243
c WORKL Real work array of length LWORKL. (OUTPUT/WORKSPACE)
244
c Private (replicated) array on each PE or array allocated on
245
c the front end. See Data Distribution Note below.
247
c LWORKL Integer. (INPUT)
248
c LWORKL must be at least 3*NCV**2 + 6*NCV.
250
c INFO Integer. (INPUT/OUTPUT)
251
c If INFO .EQ. 0, a randomly initial residual vector is used.
252
c If INFO .NE. 0, RESID contains the initial residual vector,
253
c possibly from a previous run.
254
c Error flag on output.
256
c = 1: Maximum number of iterations taken.
257
c All possible eigenvalues of OP has been found. IPARAM(5)
258
c returns the number of wanted converged Ritz values.
259
c = 2: No longer an informational error. Deprecated starting
260
c with release 2 of ARPACK.
261
c = 3: No shifts could be applied during a cycle of the
262
c Implicitly restarted Arnoldi iteration. One possibility
263
c is to increase the size of NCV relative to NEV.
264
c See remark 4 below.
265
c = -1: N must be positive.
266
c = -2: NEV must be positive.
267
c = -3: NCV-NEV >= 2 and less than or equal to N.
268
c = -4: The maximum number of Arnoldi update iteration
269
c must be greater than zero.
270
c = -5: WHICH must be one of 'LM', 'SM', 'LR', 'SR', 'LI', 'SI'
271
c = -6: BMAT must be one of 'I' or 'G'.
272
c = -7: Length of private work array is not sufficient.
273
c = -8: Error return from LAPACK eigenvalue calculation;
274
c = -9: Starting vector is zero.
275
c = -10: IPARAM(7) must be 1,2,3,4.
276
c = -11: IPARAM(7) = 1 and BMAT = 'G' are incompatable.
277
c = -12: IPARAM(1) must be equal to 0 or 1.
278
c = -9999: Could not build an Arnoldi factorization.
279
c IPARAM(5) returns the size of the current Arnoldi
283
c 1. The computed Ritz values are approximate eigenvalues of OP. The
284
c selection of WHICH should be made with this in mind when
285
c Mode = 3 and 4. After convergence, approximate eigenvalues of the
286
c original problem may be obtained with the ARPACK subroutine sneupd.
288
c 2. If a basis for the invariant subspace corresponding to the converged Ritz
289
c values is needed, the user must call sneupd immediately following
290
c completion of snaupd. This is new starting with release 2 of ARPACK.
292
c 3. If M can be factored into a Cholesky factorization M = LL`
293
c then Mode = 2 should not be selected. Instead one should use
294
c Mode = 1 with OP = inv(L)*A*inv(L`). Appropriate triangular
295
c linear systems should be solved with L and L` rather
296
c than computing inverses. After convergence, an approximate
297
c eigenvector z of the original problem is recovered by solving
298
c L`z = x where x is a Ritz vector of OP.
300
c 4. At present there is no a-priori analysis to guide the selection
301
c of NCV relative to NEV. The only formal requrement is that NCV > NEV + 2.
302
c However, it is recommended that NCV .ge. 2*NEV+1. If many problems of
303
c the same type are to be solved, one should experiment with increasing
304
c NCV while keeping NEV fixed for a given test problem. This will
305
c usually decrease the required number of OP*x operations but it
306
c also increases the work and storage required to maintain the orthogonal
307
c basis vectors. The optimal "cross-over" with respect to CPU time
308
c is problem dependent and must be determined empirically.
309
c See Chapter 8 of Reference 2 for further information.
311
c 5. When IPARAM(1) = 0, and IDO = 3, the user needs to provide the
312
c NP = IPARAM(8) real and imaginary parts of the shifts in locations
313
c real part imaginary part
314
c ----------------------- --------------
315
c 1 WORKL(IPNTR(14)) WORKL(IPNTR(14)+NP)
316
c 2 WORKL(IPNTR(14)+1) WORKL(IPNTR(14)+NP+1)
320
c NP WORKL(IPNTR(14)+NP-1) WORKL(IPNTR(14)+2*NP-1).
322
c Only complex conjugate pairs of shifts may be applied and the pairs
323
c must be placed in consecutive locations. The real part of the
324
c eigenvalues of the current upper Hessenberg matrix are located in
325
c WORKL(IPNTR(6)) through WORKL(IPNTR(6)+NCV-1) and the imaginary part
326
c in WORKL(IPNTR(7)) through WORKL(IPNTR(7)+NCV-1). They are ordered
327
c according to the order defined by WHICH. The complex conjugate
328
c pairs are kept together and the associated Ritz estimates are located in
329
c WORKL(IPNTR(8)), WORKL(IPNTR(8)+1), ... , WORKL(IPNTR(8)+NCV-1).
331
c-----------------------------------------------------------------------
333
c\Data Distribution Note:
337
c Real resid(n), v(ldv,ncv), workd(3*n), workl(lworkl)
338
c decompose d1(n), d2(n,ncv)
339
c align resid(i) with d1(i)
340
c align v(i,j) with d2(i,j)
341
c align workd(i) with d1(i) range (1:n)
342
c align workd(i) with d1(i-n) range (n+1:2*n)
343
c align workd(i) with d1(i-2*n) range (2*n+1:3*n)
344
c distribute d1(block), d2(block,:)
345
c replicated workl(lworkl)
349
c Real resid(n), v(ldv,ncv), workd(n,3), workl(lworkl)
350
c shared resid(block), v(block,:), workd(block,:)
351
c replicated workl(lworkl)
356
c-----------------------------------------------------------------------
358
c include 'ex-nonsym.doc'
360
c-----------------------------------------------------------------------
368
c 1. D.C. Sorensen, "Implicit Application of Polynomial Filters in
369
c a k-Step Arnoldi Method", SIAM J. Matr. Anal. Apps., 13 (1992),
371
c 2. R.B. Lehoucq, "Analysis and Implementation of an Implicitly
372
c Restarted Arnoldi Iteration", Rice University Technical Report
373
c TR95-13, Department of Computational and Applied Mathematics.
374
c 3. B.N. Parlett & Y. Saad, "Complex Shift and Invert Strategies for
375
c Real Matrices", Linear Algebra and its Applications, vol 88/89,
376
c pp 575-595, (1987).
379
c snaup2 ARPACK routine that implements the Implicitly Restarted
381
c ivout ARPACK utility routine that prints integers.
382
c second ARPACK utility routine for timing.
383
c svout ARPACK utility routine that prints vectors.
384
c slamch LAPACK routine that determines machine constants.
387
c Danny Sorensen Phuong Vu
388
c Richard Lehoucq CRPC / Rice University
389
c Dept. of Computational & Houston, Texas
390
c Applied Mathematics
395
c 12/16/93: Version '1.1'
397
c\SCCS Information: @(#)
398
c FILE: naupd.F SID: 2.10 DATE OF SID: 08/23/02 RELEASE: 2
404
c-----------------------------------------------------------------------
407
& ( ido, bmat, n, which, nev, tol, resid, ncv, v, ldv, iparam,
408
& ipntr, workd, workl, lworkl, info )
410
c %----------------------------------------------------%
411
c | Include files for debugging and timing information |
412
c %----------------------------------------------------%
417
c %------------------%
418
c | Scalar Arguments |
419
c %------------------%
421
character bmat*1, which*2
422
integer ido, info, ldv, lworkl, n, ncv, nev
426
c %-----------------%
427
c | Array Arguments |
428
c %-----------------%
430
integer iparam(11), ipntr(14)
432
& resid(n), v(ldv,ncv), workd(3*n), workl(lworkl)
440
parameter (one = 1.0E+0, zero = 0.0E+0)
446
integer bounds, ierr, ih, iq, ishift, iupd, iw,
447
& ldh, ldq, levec, mode, msglvl, mxiter, nb,
448
& nev0, next, np, ritzi, ritzr, j
449
save bounds, ih, iq, ishift, iupd, iw, ldh, ldq,
450
& levec, mode, msglvl, mxiter, nb, nev0, next,
453
c %----------------------%
454
c | External Subroutines |
455
c %----------------------%
457
external snaup2, svout, ivout, second, sstatn
459
c %--------------------%
460
c | External Functions |
461
c %--------------------%
467
c %-----------------------%
468
c | Executable Statements |
469
c %-----------------------%
473
c %-------------------------------%
474
c | Initialize timing statistics |
475
c | & message level for debugging |
476
c %-------------------------------%
493
c %--------------------------------------------%
494
c | Revision 2 performs only implicit restart. |
495
c %--------------------------------------------%
502
else if (nev .le. 0) then
504
else if (ncv .le. nev+1 .or. ncv .gt. n) then
506
else if (mxiter .le. 0) then
508
else if (which .ne. 'LM' .and.
509
& which .ne. 'SM' .and.
510
& which .ne. 'LR' .and.
511
& which .ne. 'SR' .and.
512
& which .ne. 'LI' .and.
513
& which .ne. 'SI') then
515
else if (bmat .ne. 'I' .and. bmat .ne. 'G') then
517
else if (lworkl .lt. 3*ncv**2 + 6*ncv) then
519
else if (mode .lt. 1 .or. mode .gt. 4) then
521
else if (mode .eq. 1 .and. bmat .eq. 'G') then
523
else if (ishift .lt. 0 .or. ishift .gt. 1) then
531
if (ierr .ne. 0) then
537
c %------------------------%
538
c | Set default parameters |
539
c %------------------------%
541
if (nb .le. 0) nb = 1
542
if (tol .le. zero) tol = slamch('EpsMach')
544
c %----------------------------------------------%
545
c | NP is the number of additional steps to |
546
c | extend the length NEV Lanczos factorization. |
547
c | NEV0 is the local variable designating the |
548
c | size of the invariant subspace desired. |
549
c %----------------------------------------------%
554
c %-----------------------------%
555
c | Zero out internal workspace |
556
c %-----------------------------%
558
do 10 j = 1, 3*ncv**2 + 6*ncv
562
c %-------------------------------------------------------------%
563
c | Pointer into WORKL for address of H, RITZ, BOUNDS, Q |
564
c | etc... and the remaining workspace. |
565
c | Also update pointer to be used on output. |
566
c | Memory is laid out as follows: |
567
c | workl(1:ncv*ncv) := generated Hessenberg matrix |
568
c | workl(ncv*ncv+1:ncv*ncv+2*ncv) := real and imaginary |
569
c | parts of ritz values |
570
c | workl(ncv*ncv+2*ncv+1:ncv*ncv+3*ncv) := error bounds |
571
c | workl(ncv*ncv+3*ncv+1:2*ncv*ncv+3*ncv) := rotation matrix Q |
572
c | workl(2*ncv*ncv+3*ncv+1:3*ncv*ncv+6*ncv) := workspace |
573
c | The final workspace is needed by subroutine sneigh called |
574
c | by snaup2. Subroutine sneigh calls LAPACK routines for |
575
c | calculating eigenvalues and the last row of the eigenvector |
577
c %-------------------------------------------------------------%
587
next = iw + ncv**2 + 3*ncv
598
c %-------------------------------------------------------%
599
c | Carry out the Implicitly restarted Arnoldi Iteration. |
600
c %-------------------------------------------------------%
603
& ( ido, bmat, n, which, nev0, np, tol, resid, mode, iupd,
604
& ishift, mxiter, v, ldv, workl(ih), ldh, workl(ritzr),
605
& workl(ritzi), workl(bounds), workl(iq), ldq, workl(iw),
606
& ipntr, workd, info )
608
c %--------------------------------------------------%
609
c | ido .ne. 99 implies use of reverse communication |
610
c | to compute operations involving OP or shifts. |
611
c %--------------------------------------------------%
613
if (ido .eq. 3) iparam(8) = np
614
if (ido .ne. 99) go to 9000
622
c %------------------------------------%
623
c | Exit if there was an informational |
624
c | error within snaup2. |
625
c %------------------------------------%
627
if (info .lt. 0) go to 9000
628
if (info .eq. 2) info = 3
630
if (msglvl .gt. 0) then
631
call ivout (logfil, 1, mxiter, ndigit,
632
& '_naupd: Number of update iterations taken')
633
call ivout (logfil, 1, np, ndigit,
634
& '_naupd: Number of wanted "converged" Ritz values')
635
call svout (logfil, np, workl(ritzr), ndigit,
636
& '_naupd: Real part of the final Ritz values')
637
call svout (logfil, np, workl(ritzi), ndigit,
638
& '_naupd: Imaginary part of the final Ritz values')
639
call svout (logfil, np, workl(bounds), ndigit,
640
& '_naupd: Associated Ritz estimates')
646
if (msglvl .gt. 0) then
648
c %--------------------------------------------------------%
649
c | Version Number & Version Date are defined in version.h |
650
c %--------------------------------------------------------%
653
write (6,1100) mxiter, nopx, nbx, nrorth, nitref, nrstrt,
654
& tmvopx, tmvbx, tnaupd, tnaup2, tnaitr, titref,
655
& tgetv0, tneigh, tngets, tnapps, tnconv, trvec
657
& 5x, '=============================================',/
658
& 5x, '= Nonsymmetric implicit Arnoldi update code =',/
659
& 5x, '= Version Number: ', ' 2.4', 21x, ' =',/
660
& 5x, '= Version Date: ', ' 07/31/96', 16x, ' =',/
661
& 5x, '=============================================',/
662
& 5x, '= Summary of timing statistics =',/
663
& 5x, '=============================================',//)
665
& 5x, 'Total number update iterations = ', i5,/
666
& 5x, 'Total number of OP*x operations = ', i5,/
667
& 5x, 'Total number of B*x operations = ', i5,/
668
& 5x, 'Total number of reorthogonalization steps = ', i5,/
669
& 5x, 'Total number of iterative refinement steps = ', i5,/
670
& 5x, 'Total number of restart steps = ', i5,/
671
& 5x, 'Total time in user OP*x operation = ', f12.6,/
672
& 5x, 'Total time in user B*x operation = ', f12.6,/
673
& 5x, 'Total time in Arnoldi update routine = ', f12.6,/
674
& 5x, 'Total time in naup2 routine = ', f12.6,/
675
& 5x, 'Total time in basic Arnoldi iteration loop = ', f12.6,/
676
& 5x, 'Total time in reorthogonalization phase = ', f12.6,/
677
& 5x, 'Total time in (re)start vector generation = ', f12.6,/
678
& 5x, 'Total time in Hessenberg eig. subproblem = ', f12.6,/
679
& 5x, 'Total time in getting the shifts = ', f12.6,/
680
& 5x, 'Total time in applying the shifts = ', f12.6,/
681
& 5x, 'Total time in convergence testing = ', f12.6,/
682
& 5x, 'Total time in computing final Ritz vectors = ', f12.6/)