This file is indexed.

/usr/include/trilinos/TbbTsqr_TbbRecursiveTsqr_Def.hpp is in libtrilinos-tpetra-dev 12.10.1-3.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
//@HEADER
// ************************************************************************
//
//          Kokkos: Node API and Parallel Node Kernels
//              Copyright (2008) Sandia Corporation
//
// Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
// the U.S. Government retains certain rights in this software.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// 3. Neither the name of the Corporation nor the names of the
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY SANDIA CORPORATION "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SANDIA CORPORATION OR THE
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Questions? Contact Michael A. Heroux (maherou@sandia.gov)
//
// ************************************************************************
//@HEADER

#ifndef __TSQR_TBB_TbbRecursiveTsqr_Def_hpp
#define __TSQR_TBB_TbbRecursiveTsqr_Def_hpp

#include <TbbTsqr_TbbRecursiveTsqr.hpp>
#include <Tsqr_Util.hpp>

// #define TBB_DEBUG 1
#ifdef TBB_DEBUG
#  include <iostream>
using std::cerr;
using std::endl;
#endif // TBB_DEBUG

////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////

namespace TSQR {
  namespace TBB {

    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    explicit_Q_helper (const size_t P_first,
                       const size_t P_last,
                       mat_view& Q_out,
                       const bool contiguous_cache_blocks) const
    {
      if (P_first > P_last || Q_out.empty ()) {
        return;
      }
      else if (P_first == P_last) {
        CacheBlocker< LocalOrdinal, Scalar >
          blocker (Q_out.nrows(), Q_out.ncols(),
                   seq_.cache_blocking_strategy());
#ifdef TBB_DEBUG
        cerr << "explicit_Q_helper: On P_first = " << P_first
             << ", filling Q_out with zeros:" << endl
             << "Q_out is " << Q_out.nrows() << " x " << Q_out.ncols()
             << " with leading dimension " << Q_out.lda() << endl;
#endif // TBB_DEBUG
        // Fill my partition with zeros.
        blocker.fill_with_zeros (Q_out, contiguous_cache_blocks);

        // If our partition is the first (topmost), fill it with
        // the first Q_out.ncols() columns of the identity matrix.
        if (P_first == 0) {
          // Fetch the topmost cache block of my partition.  Its
          // leading dimension should be set correctly by
          // top_block().
          mat_view Q_out_top =
            blocker.top_block (Q_out, contiguous_cache_blocks);

          for (LocalOrdinal j = 0; j < Q_out_top.ncols(); ++j)
            Q_out_top(j,j) = Scalar(1);
        }
      }
      else {
        // Recurse on two intervals: [P_first, P_mid] and [P_mid+1, P_last]
        const size_t P_mid = (P_first + P_last) / 2;
        split_t Q_out_split =
          partitioner_.split (Q_out, P_first, P_mid, P_last,
                              contiguous_cache_blocks);
        explicit_Q_helper (P_first, P_mid, Q_out_split.first,
                           contiguous_cache_blocks);
        explicit_Q_helper (P_mid+1, P_last, Q_out_split.second,
                           contiguous_cache_blocks);
      }
    }


    template< class LocalOrdinal, class Scalar >
    typename TbbRecursiveTsqr< LocalOrdinal, Scalar >::mat_view
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    factor_helper (const size_t P_first,
                   const size_t P_last,
                   const size_t depth,
                   mat_view A,
                   std::vector<typename TbbRecursiveTsqr<LocalOrdinal, Scalar>::SeqOutput>& seq_outputs,
                   typename TbbRecursiveTsqr<LocalOrdinal, Scalar>::ParOutput& par_outputs,
                   Scalar R[],
                   const LocalOrdinal ldr,
                   const bool contiguous_cache_blocks) const
    {
      mat_view A_top;
      if (P_first > P_last || A.empty()) {
        return A;
      }
      else if (P_first == P_last) {
        std::pair<SeqOutput, mat_view> results =
          seq_.factor (A.nrows(), A.ncols(), A.get(), A.lda(),
                       contiguous_cache_blocks);
        seq_outputs[P_first] = results.first;
        A_top = A;
      }
      else {
        // Recurse on two intervals: [P_first, P_mid] and [P_mid+1, P_last]
        const size_t P_mid = (P_first + P_last) / 2;
        split_t A_split =
          partitioner_.split (A, P_first, P_mid, P_last,
                              contiguous_cache_blocks);
        A_top = factor_helper (P_first, P_mid, depth+1, A_split.first,
                               seq_outputs, par_outputs, R, ldr,
                               contiguous_cache_blocks);
        mat_view A_bot =
          factor_helper (P_mid+1, P_last, depth+1, A_split.second,
                         seq_outputs, par_outputs, R, ldr,
                         contiguous_cache_blocks);
        // Combine the two results
        factor_pair (P_first, P_mid+1, A_top, A_bot, par_outputs,
                     contiguous_cache_blocks);
      }

      // If we're completely done, extract the final R factor from
      // the topmost partition.
      if (depth == 0) {
#ifdef TBB_DEBUG
        cerr << "factor_helper: On P_first = " << P_first
             << ", extracting R:" << endl
             << "A_top is " << A_top.nrows() << " x " << A_top.ncols()
             << " with leading dimension " << A_top.lda();
#endif // TBB_DEBUG
        seq_.extract_R (A_top.nrows(), A_top.ncols(), A_top.get(),
                        A_top.lda(), R, ldr, contiguous_cache_blocks);
      }
      return A_top;
    }


    template< class LocalOrdinal, class Scalar >
    bool
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    apply_helper_empty (const size_t P_first,
                        const size_t P_last,
                        const_mat_view& Q,
                        mat_view& C) const
    {
      if (Q.empty ()) {
        if (! C.empty())
          throw std::logic_error("Q is empty but C is not!");
        else
          return true;
      }
      else if (C.empty()) {
        if (! Q.empty())
          throw std::logic_error("C is empty but Q is not!");
        else
          return true;
      }
      else if (P_first > P_last)
        return true;
      else
        return false;
    }


    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    build_partition_array (const size_t P_first,
                           const size_t P_last,
                           typename TbbRecursiveTsqr< LocalOrdinal, Scalar >::array_top_blocks_t& top_blocks,
                           const_mat_view& Q,
                           mat_view& C,
                           const bool contiguous_cache_blocks) const
    {
#ifdef TBB_DEBUG
      cerr << "build_partition_array: [" << P_first << ", " << P_last << "]:" << endl
           << "Q is " << Q.nrows() << " x " << Q.ncols() << " w/ LDA = "
           << Q.lda() << endl << "C is " << C.nrows() << " x " << C.ncols()
           << " w/ LDA = " << C.lda() << endl;
#endif // TBB_DEBUG

      if (P_first > P_last)
        return;
      else if (P_first == P_last)
        {
          CacheBlocker< LocalOrdinal, Scalar > blocker (Q.nrows(), Q.ncols(), seq_.cache_blocking_strategy());
          const_mat_view Q_top = blocker.top_block (Q, contiguous_cache_blocks);
          mat_view C_top = blocker.top_block (C, contiguous_cache_blocks);
          top_blocks[P_first] =
            std::make_pair (const_mat_view (Q_top.ncols(), Q_top.ncols(), Q_top.get(), Q_top.lda()),
                            mat_view (C_top.ncols(), C_top.ncols(), C_top.get(), C_top.lda()));
        }
      else
        {
          // Recurse on two intervals: [P_first, P_mid] and [P_mid+1, P_last]
          const size_t P_mid = (P_first + P_last) / 2;
          const_split_t Q_split =
            partitioner_.split (Q, P_first, P_mid, P_last,
                                contiguous_cache_blocks);
          split_t C_split =
            partitioner_.split (C, P_first, P_mid, P_last,
                                contiguous_cache_blocks);
          build_partition_array (P_first, P_mid, top_blocks, Q_split.first,
                                 C_split.first, contiguous_cache_blocks);
          build_partition_array (P_mid+1, P_last, top_blocks, Q_split.second,
                                 C_split.second, contiguous_cache_blocks);
        }
    }


    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    apply_helper (const size_t P_first,
                  const size_t P_last,
                  const_mat_view Q,
                  mat_view C,
                  typename TbbRecursiveTsqr< LocalOrdinal, Scalar >::array_top_blocks_t& top_blocks,
                  const FactorOutput& factor_output,
                  const bool contiguous_cache_blocks) const
    {
      typedef std::pair< const_mat_view, mat_view > apply_t;
#ifdef TBB_DEBUG
      cerr << "apply_helper: [" << P_first << ", " << P_last << "]:" << endl
           << "Q is " << Q.nrows() << " x " << Q.ncols() << " w/ LDA = "
           << Q.lda() << endl << "C is " << C.nrows() << " x " << C.ncols()
           << " w/ LDA = " << C.lda() << endl;
#endif // TBB_DEBUG

      if (apply_helper_empty (P_first, P_last, Q, C))
        return;
      else if (P_first == P_last)
        {
          const std::vector< SeqOutput >& seq_outputs = factor_output.first;
          seq_.apply ("N", Q.nrows(), Q.ncols(), Q.get(), Q.lda(),
                      seq_outputs[P_first], C.ncols(), C.get(),
                      C.lda(), contiguous_cache_blocks);
#ifdef TBB_DEBUG
          cerr << "BOO!!!" << endl;
#endif // TBB_DEBUG
        }
      else
        {
          // Recurse on two intervals: [P_first, P_mid] and [P_mid+1, P_last]
          const size_t P_mid = (P_first + P_last) / 2;
          const_split_t Q_split =
            partitioner_.split (Q, P_first, P_mid, P_last,
                                contiguous_cache_blocks);
          split_t C_split =
            partitioner_.split (C, P_first, P_mid, P_last,
                                contiguous_cache_blocks);
          const ParOutput& par_output = factor_output.second;

          apply_pair ("N", P_first, P_mid+1, top_blocks[P_mid+1].first,
                      par_output, top_blocks[P_first].second,
                      top_blocks[P_mid+1].second, contiguous_cache_blocks);
          apply_helper (P_first, P_mid, Q_split.first, C_split.first,
                        top_blocks, factor_output, contiguous_cache_blocks);
          apply_helper (P_mid+1, P_last, Q_split.second, C_split.second,
                        top_blocks, factor_output, contiguous_cache_blocks);
        }
    }


    template< class LocalOrdinal, class Scalar >
    typename TbbRecursiveTsqr< LocalOrdinal, Scalar >::top_blocks_t
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    apply_transpose_helper (const std::string& op,
                            const size_t P_first,
                            const size_t P_last,
                            const_mat_view Q,
                            mat_view C,
                            const typename TbbRecursiveTsqr<LocalOrdinal, Scalar>::FactorOutput& factor_output,
                            const bool contiguous_cache_blocks) const
    {
      if (apply_helper_empty (P_first, P_last, Q, C)) {
        return std::make_pair (Q, C);
      }
      else if (P_first == P_last) {
        const std::vector<SeqOutput>& seq_outputs = factor_output.first;
        seq_.apply (op, Q.nrows(), Q.ncols(), Q.get(), Q.lda(),
                    seq_outputs[P_first], C.ncols(), C.get(),
                    C.lda(), contiguous_cache_blocks);
        return std::make_pair (Q, C);
      }
      else {
        // Recurse on two intervals: [P_first, P_mid] and [P_mid+1, P_last]
        const size_t P_mid = (P_first + P_last) / 2;

        const_split_t Q_split =
          partitioner_.split (Q, P_first, P_mid, P_last,
                              contiguous_cache_blocks);
        split_t C_split =
          partitioner_.split (C, P_first, P_mid, P_last,
                              contiguous_cache_blocks);
        const ParOutput& par_output = factor_output.second;
        top_blocks_t Top =
          apply_transpose_helper (op, P_first, P_mid, Q_split.first,
                                  C_split.first, factor_output,
                                  contiguous_cache_blocks);
        top_blocks_t Bottom =
          apply_transpose_helper (op, P_mid+1, P_last, Q_split.second,
                                  C_split.second, factor_output,
                                  contiguous_cache_blocks);
        apply_pair (op, P_first, P_mid+1, Bottom.first,
                    par_output, Top.second, Bottom.second,
                    contiguous_cache_blocks);
        return Top;
      }
    }


    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    factor_pair (const size_t P_top,
                 const size_t P_bot,
                 mat_view& A_top,
                 mat_view& A_bot,
                 std::vector< std::vector< Scalar > >& par_outputs,
                 const bool contiguous_cache_blocks) const
    {
      if (P_top == P_bot)
        {
          throw std::logic_error("factor_pair: should never get here!");
          return; // to pacify the compiler
        }
      // We only read and write the upper ncols x ncols triangle of
      // each block.
      const LocalOrdinal ncols = A_top.ncols();
      if (A_bot.ncols() != ncols)
        throw std::logic_error("A_bot.ncols() != A_top.ncols()");

      std::vector< Scalar >& tau = par_outputs[P_bot];
      std::vector< Scalar > work (ncols);

      TSQR::Combine< LocalOrdinal, Scalar > combine_;
      combine_.factor_pair (ncols, A_top.get(), A_top.lda(),
                            A_bot.get(), A_bot.lda(), &tau[0], &work[0]);
    }

    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    apply_pair (const std::string& trans,
                const size_t P_top,
                const size_t P_bot,
                const_mat_view& Q_bot,
                const std::vector<std::vector<Scalar> >& tau_arrays,
                mat_view& C_top,
                mat_view& C_bot,
                const bool contiguous_cache_blocks) const
    {
      if (P_top == P_bot) {
        throw std::logic_error ("apply_pair: should never get here!");
      }
      const std::vector<Scalar>& tau = tau_arrays[P_bot];
      std::vector<Scalar> work (C_top.ncols());

      TSQR::Combine<LocalOrdinal, Scalar> combine_;
      combine_.apply_pair (trans.c_str(), C_top.ncols(), Q_bot.ncols(),
                           Q_bot.get(), Q_bot.lda(), &tau[0],
                           C_top.get(), C_top.lda(),
                           C_bot.get(), C_bot.lda(), &work[0]);
    }

    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    cache_block_helper (mat_view& A_out,
                        const_mat_view& A_in,
                        const size_t P_first,
                        const size_t P_last) const
    {
      if (P_first > P_last)
        return;
      else if (P_first == P_last)
        seq_.cache_block (A_out.nrows(), A_out.ncols(), A_out.get(),
                          A_in.get(), A_in.lda());
      else
        {
          const size_t P_mid = (P_first + P_last) / 2;
          const_split_t A_in_split =
            partitioner_.split (A_in, P_first, P_mid, P_last, false);
          split_t A_out_split =
            partitioner_.split (A_out, P_first, P_mid, P_last, true);
          cache_block_helper (A_out_split.first, A_in_split.first,
                              P_first, P_mid);
          cache_block_helper (A_out_split.second, A_in_split.second,
                              P_mid+1, P_last);
        }
    }

    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    un_cache_block_helper (mat_view& A_out,
                           const const_mat_view& A_in,
                           const size_t P_first,
                           const size_t P_last) const
    {
      if (P_first > P_last) {
        return;
      }
      else if (P_first == P_last) {
        seq_.un_cache_block (A_out.nrows(), A_out.ncols(), A_out.get(),
                             A_out.lda(), A_in.get());
      }
      else {
        const size_t P_mid = (P_first + P_last) / 2;
        const const_split_t A_in_split =
          partitioner_.split (A_in, P_first, P_mid, P_last, true);
        split_t A_out_split =
          partitioner_.split (A_out, P_first, P_mid, P_last, false);

        un_cache_block_helper (A_out_split.first, A_in_split.first,
                               P_first, P_mid);
        un_cache_block_helper (A_out_split.second, A_in_split.second,
                               P_mid+1, P_last);
      }
    }

    template< class LocalOrdinal, class Scalar >
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    TbbRecursiveTsqr (const size_t num_cores,
                      const size_t cache_size_hint)
      : seq_ (cache_size_hint), ncores_ (1)
    {
      if (num_cores < 1)
        ncores_ = 1; // default is no parallelism
      else
        ncores_ = num_cores;
    }

    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    cache_block (const LocalOrdinal nrows,
                 const LocalOrdinal ncols,
                 Scalar A_out[],
                 const Scalar A_in[],
                 const LocalOrdinal lda_in) const
    {
      const_mat_view A_in_view (nrows, ncols, A_in, lda_in);
      // Leading dimension doesn't matter, since we're going to cache block it.
      mat_view A_out_view (nrows, ncols, A_out, lda_in);
      cache_block_helper (A_out_view, A_in_view, 0, ncores()-1);
    }

    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    un_cache_block (const LocalOrdinal nrows,
                    const LocalOrdinal ncols,
                    Scalar A_out[],
                    const LocalOrdinal lda_out,
                    const Scalar A_in[]) const
    {
      // Leading dimension doesn't matter, since it's cache-blocked.
      const_mat_view A_in_view (nrows, ncols, A_in, lda_out);
      mat_view A_out_view (nrows, ncols, A_out, lda_out);
      un_cache_block_helper (A_out_view, A_in_view, 0, ncores()-1);
    }

    template< class LocalOrdinal, class Scalar >
    typename TbbRecursiveTsqr< LocalOrdinal, Scalar >::FactorOutput
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    factor (const LocalOrdinal nrows,
            const LocalOrdinal ncols,
            Scalar A[],
            const LocalOrdinal lda,
            Scalar R[],
            const LocalOrdinal ldr,
            const bool contiguous_cache_blocks) const
    {
      mat_view A_view (nrows, ncols, A, lda);
      std::vector< SeqOutput > seq_outputs (ncores());
      ParOutput par_outputs (ncores(), std::vector< Scalar >(ncols));
      (void) factor_helper (0, ncores()-1, 0, A_view, seq_outputs,
                            par_outputs, R, ldr, contiguous_cache_blocks);
      return std::make_pair (seq_outputs, par_outputs);
    }

    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    apply (const std::string& op,
           const LocalOrdinal nrows,
           const LocalOrdinal ncols_C,
           Scalar C[],
           const LocalOrdinal ldc,
           const LocalOrdinal ncols_Q,
           const Scalar Q[],
           const LocalOrdinal ldq,
           const typename TbbRecursiveTsqr< LocalOrdinal, Scalar >::FactorOutput& factor_output,
           const bool contiguous_cache_blocks) const
    {
      const ApplyType apply_type (op);
      if (apply_type == ApplyType::ConjugateTranspose &&
          Teuchos::ScalarTraits<Scalar>::isComplex)
        throw std::logic_error("Applying Q^H for complex scalar types "
                               "not yet implemented");

      const_mat_view Q_view (nrows, ncols_Q, Q, ldq);
      mat_view C_view (nrows, ncols_C, C, ldc);
      if (! apply_type.transposed ()) {
        array_top_blocks_t top_blocks (ncores ());
        build_partition_array (0, ncores () - 1, top_blocks, Q_view,
                               C_view, contiguous_cache_blocks);
        apply_helper (0, ncores () - 1, Q_view, C_view, top_blocks,
                      factor_output, contiguous_cache_blocks);
      }
      else {
        apply_transpose_helper (op, 0, ncores () - 1, Q_view, C_view,
                                factor_output, contiguous_cache_blocks);
      }
    }


    template< class LocalOrdinal, class Scalar >
    void
    TbbRecursiveTsqr< LocalOrdinal, Scalar >::
    explicit_Q (const LocalOrdinal nrows,
                const LocalOrdinal ncols_Q_in,
                const Scalar Q_in[],
                const LocalOrdinal ldq_in,
                const LocalOrdinal ncols_Q_out,
                Scalar Q_out[],
                const LocalOrdinal ldq_out,
                const typename TbbRecursiveTsqr< LocalOrdinal, Scalar >::FactorOutput& factor_output,
                const bool contiguous_cache_blocks) const
    {
      if (ncols_Q_out != ncols_Q_in)
        throw std::logic_error("FIXME Currently, explicit_Q() only works for ncols_Q_out == ncols_Q_in");

      const_mat_view Q_in_view (nrows, ncols_Q_in, Q_in, ldq_in);
      mat_view Q_out_view (nrows, ncols_Q_out, Q_out, ldq_out);

      explicit_Q_helper (0, ncores()-1, Q_out_view, contiguous_cache_blocks);
      apply ("N", nrows, ncols_Q_out, Q_out, ldq_out, ncols_Q_in,
             Q_in, ldq_in, factor_output, contiguous_cache_blocks);
    }

  } // namespace TBB
} // namespace TSQR


#endif // __TSQR_TBB_TbbRecursiveTsqr_Def_hpp