Minor clean up for cooley tukey in C++ #276
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mika314
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Jul 19, 2018
mika314
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- rename c64 to complex
- make pi a constant instead of function
- fix complilation warnings about comparing signed int with unsigned int
Gathros
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Implementation Edit
| auto temp = std::vector<c64>(size / 2); | ||
| for (size_t i = 0; i < size / 2; ++i) { | ||
| auto temp = std::vector<complex>(size / 2); | ||
| for (int i = 0; i < size / 2; ++i) { |
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Similarly to the other PR, this should actually be ptrdiff_t
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Copy from the other PR:
@Gustorn I decided to use int instead of ptrdiff_t to improve the readability of the code, not to many people know about ptrdiff_t. And to overflow int on modern computers for vector of complex values we would need to have 2 billions elements in the array which will consume 8 (for double) * 2 (for real and imaginary) * 2 (billions elements) = 32 GB of memory. Kind of unlikely.
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Since your changing the code, can you add the |
- rename c64 to complex - make pi a constant instead of function - fix complilation warnings about comparing signed int with unsigned int
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| for (auto i = 0; i < N; ++i) { | ||
| for (auto j = 0; j < N; ++j) { | ||
| using namespace std::literals::complex_literals; | ||
| tmp[i] += X[j] * exp(-2.0 * M_PI * i * j / N * 1i); |
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Why not do this, tmp[i] += X[j] * exp(complex(0, -2.0 * M_PI * i * j / N));.
