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#include "fourier.hpp"
#include <getopt.h>
#include <iostream>
#include <fstream>
int main(int argc, char* argv[]) {
unsigned p = 2;
unsigned s = 2;
Real λ = 0.5;
Real τ₀ = 0;
Real β₀ = 0;
Real yₘₐₓ = 0.5;
Real Δy = 0.05;
unsigned log2n = 8;
Real τₘₐₓ = 20;
unsigned maxIterations = 1000;
Real ε = 1e-14;
Real γ = 1;
int opt;
while ((opt = getopt(argc, argv, "p:s:2:T:t:0:y:d:I:g:l")) != -1) {
switch (opt) {
case 'p':
p = atoi(optarg);
break;
case 's':
s = atoi(optarg);
break;
case '2':
log2n = atoi(optarg);
break;
case 'T':
τₘₐₓ = atof(optarg);
break;
case 't':
τ₀ = atof(optarg);
break;
case '0':
β₀ = atof(optarg);
break;
case 'y':
yₘₐₓ = atof(optarg);
break;
case 'd':
Δy = atof(optarg);
break;
case 'I':
maxIterations = (unsigned)atof(optarg);
break;
case 'g':
γ = atof(optarg);
break;
default:
exit(1);
}
}
unsigned N = pow(2, log2n);
Real Δτ = 1e-2;
Real Δω = 1e-2;
Real Δs = 1e-2;
Real k = 0.1;
Real Γ₀ = 1.0;
Real μ = Γ₀;
if (τ₀ > 0) {
μ = (sqrt(1+4*Γ₀*τ₀)-1)/(2*τ₀);
}
std::vector<Real> C(N);
std::vector<Real> R(N);
LogarithmicFourierTransform fft(N, k, Δω, Δτ, Δs);
for (unsigned n = 0; n < N; n++) {
if (τ₀ > 0) {
C[n] = Γ₀ * (exp(-μ * fft.t(n)) - μ * τ₀ * exp(-fft.t(n) / τ₀)) / (μ - pow(μ, 3) * pow(τ₀, 2));
} else {
C[n] = Γ₀ * exp(-μ * fft.t(n)) / μ;
}
R[n] = exp(-μ * fft.t(n));
}
std::vector<Complex> Ct = fft.fourier(C, true);
std::vector<Complex> Rt = fft.fourier(R, false);
/*
for (unsigned n = 0; n < N; n++) {
std::cout << fft.t(n) << " " << C[n] << std::endl;
}
*/
for (unsigned n = 0; n < N; n++) {
std::cout << fft.ν(n) << " " << Ct[n].real() << std::endl;
}
/*
// start from the exact solution for τ₀ = 0
for (unsigned i = 0; i < N + 1; i++) {
Real ω = i * Δω;
Ct[i] = 2 * Γ₀ / (pow(μ, 2) + pow(ω, 2)) / (1 + pow(τ₀ * ω, 2));
Rt[i] = 1.0 / (μ + 1i * ω);
Γt[i] = Γ₀ / (1 + pow(τ₀ * ω, 2));
}
C = fft.inverse(Ct);
R = fft.inverse(Rt);
*/
return 0;
}
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