c++ - Doing permutation of the dimension in a Boost multi_array -


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i'm writing c++ program using boost multi_array library. have 4-dimensional array with, example, shape of [5][10][100][20]. , change shape of array [100][10][5][20]. proper way this?

thank you

assuming ask reshaping , not permutation of dimensions (those operations not same), can use reshape member function of boost::multi_array, (example taken verbatim boost multi-array documentation)

typedef boost::multi_array<double, 3> array_type;  array_type::extent_gen extents; array_type a(extents[2][3][4]); boost::array<array_type::index, 3> dims = {{4, 3, 2}};        a.reshape(dims);

full example below:

#include <iostream> #include <boost/multi_array.hpp>  int main() {     using array_type = boost::multi_array<double, 2>;      array_type::extent_gen extents;     array_type a(extents[1][2]); // 1 x 2 array      a[0][0] = 1; a[0][1] = 2;     std::cout << a[0][0] << ' ' << a[0][1] << '\n';      boost::array<array_type::index, 2> dims = {{2,1}};     a.reshape(dims); // reshape 2 x 1      std::cout << a[0][0] << ' ' << a[1][0] << '\n'; // verify }

live on wandbox

as dimension permutation, far know boost::multi_array not have function that, you'd need write own.


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