1 // Copyright 2008 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 // resize_from_other.cpp - an experiment in writing a resize function for
15 // multi_arrays that will use the extents from another to build itself.
16 //
17
18 #include <boost/multi_array.hpp>
19 #include <boost/static_assert.hpp>
20 #include <boost/array.hpp>
21 #include <algorithm>
22
23 template <typename T, typename U, std::size_t N>
24 void
resize_from_MultiArray(boost::multi_array<T,N> & marray,U & other)25 resize_from_MultiArray(boost::multi_array<T,N>& marray, U& other) {
26
27 // U must be a model of MultiArray
28 boost::function_requires<
29 boost::multi_array_concepts::ConstMultiArrayConcept<U,U::dimensionality> >();
30 // U better have U::dimensionality == N
31 BOOST_STATIC_ASSERT(U::dimensionality == N);
32
33 boost::array<typename boost::multi_array<T,N>::size_type, N> shape;
34
35 std::copy(other.shape(), other.shape()+N, shape.begin());
36
37 marray.resize(shape);
38
39 }
40
41 #include <iostream>
42
43
main()44 int main () {
45
46 boost::multi_array<int,2> A(boost::extents[5][4]), B;
47 boost::multi_array<int,3> C;
48
49 resize_from_MultiArray(B,A);
50
51 #if 0
52 resize_from_MultiArray(C,A); // Compile-time error
53 #endif
54
55 std::cout << B.shape()[0] << ", " << B.shape()[1] << '\n';
56
57 }
58