1// Copyright 2002 The Trustees of Indiana University.
2
3// Use, modification and distribution is subject to the Boost Software
4// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
5// http://www.boost.org/LICENSE_1_0.txt)
6
7// Boost.MultiArray Library
8// Authors: Ronald Garcia
9// Jeremy Siek
10// Andrew Lumsdaine
11// See http://www.boost.org/libs/multi_array for documentation.
12
13//
14// reshape.cpp - testing reshaping functionality
15//
16
17#include <boost/multi_array.hpp>
18
19#include <boost/core/lightweight_test.hpp>
20
21#include <boost/array.hpp>
22#include <boost/type.hpp>
23
24int
25main()
26{
27 const int ndims=3;
28 typedef boost::multi_array<int,ndims> array;
29 typedef boost::multi_array_ref<int,ndims> array_ref;
30 typedef boost::const_multi_array_ref<int,ndims> const_array_ref;
31
32 boost::array<array::size_type,ndims> dims = {.elems: {2,3,4}};
33 boost::array<array::size_type,ndims> new_dims = {.elems: {4,3,2}};
34
35 int data[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,
36 14,15,16,17,18,19,20,21,22,23};
37 const int data_size=24;
38
39 // Basic reshape test
40 {
41 array A(dims);
42 A.assign(begin: data,end: data+data_size);
43
44 array_ref B(data,dims);
45 const_array_ref C(data,dims);
46
47 A.reshape(extents: new_dims);
48 B.reshape(extents: new_dims);
49 C.reshape(extents: new_dims);
50
51 int* ptr = data;
52 for (array::index i = 0; i != 4; ++i)
53 for (array::index j = 0; j != 3; ++j)
54 for (array::index k = 0; k != 2; ++k) {
55 BOOST_TEST(A[i][j][k] == *ptr);
56 BOOST_TEST(B[i][j][k] == *ptr);
57 BOOST_TEST(C[i][j][k] == *ptr++);
58 }
59 }
60
61 // Ensure that index bases are preserved over reshape
62 {
63 boost::array<array::index,ndims> bases = {.elems: {0, 1, -1}};
64
65 array A(dims);
66 A.assign(begin: data,end: data+data_size);
67
68 array_ref B(data,dims);
69 const_array_ref C(data,dims);
70
71 A.reindex(values: bases);
72 B.reindex(values: bases);
73 C.reindex(values: bases);
74
75 A.reshape(extents: new_dims);
76 B.reshape(extents: new_dims);
77 C.reshape(extents: new_dims);
78
79 int* ptr = data;
80 for (array::index i = 0; i != 4; ++i)
81 for (array::index j = 1; j != 4; ++j)
82 for (array::index k = -1; k != 1; ++k) {
83 BOOST_TEST(A[i][j][k] == *ptr);
84 BOOST_TEST(B[i][j][k] == *ptr);
85 BOOST_TEST(C[i][j][k] == *ptr++);
86 }
87 }
88
89 return boost::report_errors();
90}
91
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98

source code of boost/libs/multi_array/test/reshape.cpp