BitMagic-C++: svsample03.cpp Source File

BitMagic-C++

svsample03.cpp
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1 /*
2 Copyright(c) 2002-2017 Anatoliy Kuznetsov(anatoliy_kuznetsov at yahoo.com)
3
4 Licensed under the Apache License, Version 2.0 (the "License");
5 you may not use this file except in compliance with the License.
6 You may obtain a copy of the License at
7
8 http://www.apache.org/licenses/LICENSE-2.0
9
10 Unless required by applicable law or agreed to in writing, software
11 distributed under the License is distributed on an "AS IS" BASIS,
12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 See the License for the specific language governing permissions and
14 limitations under the License.
15
16 For more information please visit: http://bitmagic.io
17 */
18
19 /** \example svsample03.cpp
20 Example of how to merge sparse vectors and extract values fast
21
22 \sa bm::sparse_vector<>::set
23 \sa bm::sparse_vector<>::import
24 \sa bm::sparse_vector<>::decode
25 \sa bm::sparse_vector<>::join
26 */
27
28 /*! \file svsample03.cpp
29 \brief Example: sparse_vector<> merge and fast extraction of content
30 */
31
32
33 #include <iostream>
34 #include <vector>
35 #include "bm.h"
36 #include "bmsparsevec.h"
37
38 using namespace std;
39
40 int main(void)
41 {
42 bm::sparse_vector<unsigned, bm::bvector<> > sv1;
43 bm::sparse_vector<unsigned, bm::bvector<> > sv2;
44 unsigned i;
45 unsigned arr[3] = {1,2,3};
46
47 sv1.import(arr, 3); // import from a C-style array (fastest way to populate)
48
49 // optimize memory allocation of sparse vector
50 {
51 BM_DECLARE_TEMP_BLOCK(tb)
52 sv1.optimize(tb);
53 }
54 cout << "sv1.size() = " << sv1.size() << ": ";
55 for (i = 0; i < sv1.size(); ++i)
56 {
57 cout << sv1.at(i) << ",";
58 }
59 cout << endl;
60
61 // populate second sparse vector using dunamic resize assignment
62 //
63 for (i = 65536; i < 65536+10; ++i)
64 {
65 sv2.set(i, 256+i);
66 }
67 cout << "sv2.size() = " << sv2.size() << endl;
68
69 cout << "Perform sparse_vector<>::join()" << endl;
70 // join sv2 into sv1
71 // operation implemented using bitset OR on all bit-planes.
72 sv1.join(sv2);
73 sv1.optimize(); // please note, we use default optimize here (it is a bit slower)
74
75 cout << "Now sv1.size() = " << sv1.size() << endl;
76
77
78 std::vector<unsigned> v1(16);
79 sv1.decode(&v1[0], 65530, 16); // extract 16 elements starting from 65530
80 for (i = 0; i < 16; ++i)
81 {
82 cout << v1[i] << ",";
83 }
84 cout << endl;
85
86
87
88 return 0;
89 }
90
bm::sparse_vector::optimize
void optimize(bm::word_t *temp_block=0, typename bvector_type::optmode opt_mode=bvector_type::opt_compress, typename sparse_vector< Val, BV >::statistics *stat=0)
run memory optimization for all vector plains
Definition: bmsparsevec.h:1728
bm::sparse_vector
sparse vector with runtime compression using bit transposition method
Definition: bmsparsevec.h:81
BM_DECLARE_TEMP_BLOCK
#define BM_DECLARE_TEMP_BLOCK(x)
Definition: bm.h:47
bmsparsevec.h
Sparse constainer sparse_vector<> for integer types using bit-transposition transform.
bm::sparse_vector::import
void import(const value_type *arr, size_type arr_size, size_type offset=0, bool set_not_null=true)
Import list of elements from a C-style array.
Definition: bmsparsevec.h:994
bm::sparse_vector::size
size_type size() const BMNOEXCEPT
return size of the vector
Definition: bmsparsevec.h:644
main
int main(void)
Definition: svsample03.cpp:40
bm::sparse_vector::at
value_type at(size_type idx) const
access specified element with bounds checking
Definition: bmsparsevec.h:1434
bm::sparse_vector::decode
size_type decode(value_type *arr, size_type idx_from, size_type dec_size, bool zero_mem=true) const
Bulk export list of elements to a C-style array.
Definition: bmsparsevec.h:1083
bm::sparse_vector::join
sparse_vector< Val, BV > & join(const sparse_vector< Val, BV > &sv)
join all with another sparse vector using OR operation
Definition: bmsparsevec.h:1764
bm.h
Compressed bit-vector bvector<> container, set algebraic methods, traversal iterators.
bm::sparse_vector::set
void set(size_type idx, value_type v)
set specified element with bounds checking and automatic resize
Definition: bmsparsevec.h:1469