mirror of
https://github.com/triqs/dft_tools
synced 2024-11-01 11:43:47 +01:00
27 lines
715 B
C++
27 lines
715 B
C++
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#include "triqs/clef.hpp"
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#include <iostream>
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using namespace triqs::clef;
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int main() {
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int N = 5;
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double pi = std::acos(-1);
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// automatic assignment of vector
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placeholder<0> k_;
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std::vector<double> V(N);
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make_expr(V)[k_] << cos((2 * pi * k_) / N);
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// chaining them ...
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placeholder<1> i_;
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std::vector<std::vector<double>> W(3, std::vector<double>(N));
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make_expr(W)[i_][k_] << i_ + cos((2 * pi * k_) / N);
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// check result...
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for (size_t u = 0; u < V.size(); ++u)
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if (std::abs(V[u] - cos((2 * pi * u) / N)) > 1.e-10) throw "error!";
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for (size_t w = 0; w < W.size(); ++w)
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for (size_t u = 0; u < W[w].size(); ++u)
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if (std::abs(W[w][u] - (w + cos((2 * pi * u) / N))) > 1.e-10) throw "error!";
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}
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