MFEM  v4.0
Finite element discretization library
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blockvector.hpp
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1 // Copyright (c) 2010, Lawrence Livermore National Security, LLC. Produced at
2 // the Lawrence Livermore National Laboratory. LLNL-CODE-443211. All Rights
3 // reserved. See file COPYRIGHT for details.
4 //
5 // This file is part of the MFEM library. For more information and source code
6 // availability see http://mfem.org.
7 //
8 // MFEM is free software; you can redistribute it and/or modify it under the
9 // terms of the GNU Lesser General Public License (as published by the Free
10 // Software Foundation) version 2.1 dated February 1999.
11 
12 #ifndef MFEM_BLOCKVECTOR
13 #define MFEM_BLOCKVECTOR
14 
15 #include "../config/config.hpp"
16 #include "../general/array.hpp"
17 #include "vector.hpp"
18 
19 namespace mfem
20 {
21 
22 //! @class BlockVector
23 /**
24  * \brief A class to handle Vectors in a block fashion
25  *
26  * All data is contained in Vector::data, while blockVector is just a viewer for
27  * this data.
28  *
29  */
30 class BlockVector: public Vector
31 {
32 protected:
33 
34  //! Number of blocks in the blockVector
35  int numBlocks;
36  //! Offset for each block start. (length numBlocks+1)
37  /**
38  * blockOffsets[i+1] - blockOffsets[i] is the size of block i.
39  *
40  * This array is not owned.
41  */
42  const int *blockOffsets;
43  //! array of Vector objects used to extract blocks without allocating memory.
44  /** This array is owned. */
46 
47  void SetBlocks();
48 
49 public:
50  //! empty constructor
51  BlockVector();
52 
53  //! Constructor
54  /**
55  * bOffsets is an array of integers (length nBlocks+1) that tells the offsets
56  * of each block start.
57  */
58  BlockVector(const Array<int> & bOffsets);
59 
60  /// Construct a BlockVector with the given MemoryType @a mt.
61  BlockVector(const Array<int> & bOffsets, MemoryType mt);
62 
63  //! Copy constructor
64  BlockVector(const BlockVector & block);
65 
66  //! View constructor
67  /**
68  * data is an array of double of length at least blockOffsets[numBlocks] that
69  * contain all the values of the monolithic vector. bOffsets is an array of
70  * integers (length nBlocks+1) that tells the offsets of each block start.
71  * nBlocks is the number of blocks.
72  */
73  BlockVector(double *data, const Array<int> & bOffsets);
74 
75  //! Assignment operator. this and original must have the same block structure.
76  BlockVector & operator=(const BlockVector & original);
77  //! Set each entry of this equal to val
78  BlockVector & operator=(double val);
79 
80  //! Destructor
81  ~BlockVector();
82 
83  //! Get the i-th vector in the block.
84  Vector & GetBlock(int i) { return blocks[i]; }
85  //! Get the i-th vector in the block (const version).
86  const Vector & GetBlock(int i) const { return blocks[i]; }
87 
88  //! Get the i-th vector in the block
89  void GetBlockView(int i, Vector & blockView);
90 
91  int BlockSize(int i) { return blockOffsets[i+1] - blockOffsets[i]; }
92 
93  //! Update method
94  /**
95  * data is an array of double of length at least blockOffsets[numBlocks] that
96  * contain all the values of the monolithic vector. bOffsets is an array of
97  * integers (length nBlocks+1) that tells the offsets of each block start.
98  * nBlocks is the number of blocks.
99  */
100  void Update(double *data, const Array<int> & bOffsets);
101 
102  /// Update a BlockVector with new @a bOffsets and make sure it owns its data.
103  /** The block-vector will be re-allocated if either:
104  - the offsets @a bOffsets are different from the current offsets, or
105  - currently, the block-vector does not own its data. */
106  void Update(const Array<int> &bOffsets);
107 
108  /** @brief Update a BlockVector with new @a bOffsets and make sure it owns
109  its data and uses the MemoryType @a mt. */
110  /** The block-vector will be re-allocated if either:
111  - the offsets @a bOffsets are different from the current offsets, or
112  - currently, the block-vector does not own its data, or
113  - currently, the block-vector does not use MemoryType @a mt. */
114  void Update(const Array<int> &bOffsets, MemoryType mt);
115 };
116 
117 }
118 
119 #endif /* MFEM_BLOCKVECTOR */
~BlockVector()
Destructor.
int BlockSize(int i)
Definition: blockvector.hpp:91
Memory< double > data
Definition: vector.hpp:52
void GetBlockView(int i, Vector &blockView)
Get the i-th vector in the block.
A class to handle Vectors in a block fashion.
Definition: blockvector.hpp:30
BlockVector()
empty constructor
Definition: blockvector.cpp:29
const int * blockOffsets
Offset for each block start. (length numBlocks+1)
Definition: blockvector.hpp:42
void Update(double *data, const Array< int > &bOffsets)
Update method.
Definition: blockvector.cpp:77
const Vector & GetBlock(int i) const
Get the i-th vector in the block (const version).
Definition: blockvector.hpp:86
int numBlocks
Number of blocks in the blockVector.
Definition: blockvector.hpp:35
BlockVector & operator=(const BlockVector &original)
Assignment operator. this and original must have the same block structure.
MemoryType
Memory types supported by MFEM.
Definition: mem_manager.hpp:27
Vector data type.
Definition: vector.hpp:48
Vector * blocks
array of Vector objects used to extract blocks without allocating memory.
Definition: blockvector.hpp:45
Vector & GetBlock(int i)
Get the i-th vector in the block.
Definition: blockvector.hpp:84