87 lines
3.3 KiB
C++
87 lines
3.3 KiB
C++
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/********************************************************
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* ██████╗ ██████╗████████╗██╗
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* ██╔════╝ ██╔════╝╚══██╔══╝██║
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* ██║ ███╗██║ ██║ ██║
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* ██║ ██║██║ ██║ ██║
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* ╚██████╔╝╚██████╗ ██║ ███████╗
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* ╚═════╝ ╚═════╝ ╚═╝ ╚══════╝
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* Geophysical Computational Tools & Library (GCTL)
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*
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* Copyright (c) 2023 Yi Zhang (yizhang-geo@zju.edu.cn)
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*
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* GCTL is distributed under a dual licensing scheme. You can redistribute
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* it and/or modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation, either version 2
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* of the License, or (at your option) any later version. You should have
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* received a copy of the GNU Lesser General Public License along with this
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* program. If not, see <http://www.gnu.org/licenses/>.
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*
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* If the terms and conditions of the LGPL v.2. would prevent you from using
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* the GCTL, please consider the option to obtain a commercial license for a
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* fee. These licenses are offered by the GCTL's original author. As a rule,
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* licenses are provided "as-is", unlimited in time for a one time fee. Please
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* send corresponding requests to: yizhang-geo@zju.edu.cn. Please do not forget
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* to include some description of your company and the realm of its activities.
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* Also add information on how to contact you by electronic and paper mail.
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******************************************************/
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#include "../lib/core.h"
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#include "../lib/io.h"
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#include "../lib/algorithm.h"
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using namespace gctl;
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double module(std::complex<double> a)
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{
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return sqrt(a.real()*a.real() + a.imag()*a.imag());
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}
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int main(int argc, char const *argv[]) try
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{
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int fs = 100;
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double T = 5;
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int n = round(fs*T);
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double t;
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gctl::array<double> in(n), out;
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gctl::array<double> freq_index;
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gctl::_1cd_array spectrum;
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for (size_t i = 0; i < n; i++)
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{
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t = 1.0*T*i/n;
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in[i] = 2.0*sin(2.0*GCTL_Pi*t*10) + 1.0*sin(2.0*GCTL_Pi*t*5) + 3.0*sin(2.0*GCTL_Pi*t*2);
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}
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// Run the r2c transform
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gctl::dft_r2c_1d(in, spectrum, 1.0*fs, &freq_index);
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std::ofstream ofile;
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open_outfile(ofile, "fft_example_spec.out");
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for (size_t i = 0; i < spectrum.size(); i++)
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{
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ofile << freq_index[i] << ' ' << module(spectrum[i]) << " ";
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if (9.5 < freq_index[i] && freq_index[i] < 10.5) {spectrum[i].real(0.0); spectrum[i].imag(0.0);}
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//if (1.5 < freq_index[i] && freq_index[i] < 2.5) {spectrum[i].real(0.0); = spectrum[i].imag(0.0);}
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if (4.5 < freq_index[i] && freq_index[i] < 5.5) {spectrum[i].real(0.0); spectrum[i].imag(0.0);}
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ofile << module(spectrum[i]) << "\n";
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}
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ofile.close();
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// Run the c2r transform
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gctl::dft_c2r_1d(spectrum, out);
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open_outfile(ofile, "fft_example_sig.out");
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for (size_t i = 0; i < n; i++)
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{
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t = 1.0*T*i/n;
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ofile << t << " " << in[i] << " " << out[i] << "\n";
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}
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ofile.close();
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}
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catch(std::exception &e)
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{
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GCTL_ShowWhatError(e.what(), GCTL_ERROR_ERROR, 0, 0, 0);
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}
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