1// Ceres Solver - A fast non-linear least squares minimizer
2// Copyright 2010, 2011, 2012 Google Inc. All rights reserved.
3// http://code.google.com/p/ceres-solver/
4//
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6// modification, are permitted provided that the following conditions are met:
7//
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9//   this list of conditions and the following disclaimer.
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12//   and/or other materials provided with the distribution.
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14//   used to endorse or promote products derived from this software without
15//   specific prior written permission.
16//
17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
18// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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28//
29// Author: sameeragarwal@google.com (Sameer Agarwal)
30
31#ifndef CERES_INTERNAL_DETECT_STRUCTURE_H_
32#define CERES_INTERNAL_DETECT_STRUCTURE_H_
33
34#include "ceres/block_structure.h"
35
36namespace ceres {
37namespace internal {
38
39// Detect static blocks in the problem sparsity. For rows containing
40// e_blocks, we are interested in detecting if the size of the row
41// blocks, e_blocks and the f_blocks remain constant. If they do, then
42// we can use template specialization to improve the performance of
43// the block level linear algebra operations used by the
44// SchurEliminator.
45//
46// If a block size is not constant, we return Eigen::Dynamic as the
47// value. This just means that the eliminator uses dynamically sized
48// linear algebra operations rather than static operations whose size
49// is known as compile time.
50//
51// For more details about e_blocks and f_blocks, see
52// schur_eliminator.h. This information is used to initialized an
53// appropriate template specialization of SchurEliminator.
54void DetectStructure(const CompressedRowBlockStructure& bs,
55                     const int num_eliminate_blocks,
56                     int* row_block_size,
57                     int* e_block_size,
58                     int* f_block_size);
59
60}  // namespace internal
61}  // namespace ceres
62
63#endif  // CERES_INTERNAL_DETECT_STRUCTURE_H_
64