Initial commit

.gitignore

+generate-points

draw.py

+import matplotlib.pyplot as plt
+import numpy as np
+
+with open('points.log') as f:
+    cont = f.read()
+
+u_arr = []
+x_arr = []
+for line in cont.split('\n'):
+    if line == '':
+        continue
+    u, x = line.split(' ')
+    iu, ix = float(u), float(x)
+    u_arr.append(iu)
+    x_arr.append(ix)
+
+
+
+
+plt.scatter(np.array(u_arr), np.array(x_arr), s=1)
+plt.show()

generate-points.cc

+#include <iostream>
+#include <array>
+#include <cassert>
+
+constexpr auto sample_per_u = 10;
+constexpr auto iteration_count = 200;
+constexpr auto sample_range_begin = 1.000;
+constexpr auto sample_range_end = 4.000;
+constexpr auto delta_u = 0.001;
+
+auto sample_after_iteration(double u) {
+    // Firstly, let's do some iterations. 
+    double x_curr = 0.01;
+    for(int i = 0; i < iteration_count; ++i) {
+        assert(x_curr > 0 && x_curr < 1);
+        x_curr = u * x_curr * (1 - x_curr);
+    }
+    // And then, take some samples.
+    std::array<double, sample_per_u> samples;
+    for(int i = 0; i < sample_per_u; ++i) {
+        samples[i] = x_curr;
+        x_curr = u * x_curr * (1 - x_curr);
+    }
+    return samples;
+}
+
+void print_points() {
+    for(auto curr_u = sample_range_begin; curr_u <= sample_range_end; curr_u += delta_u) {
+        auto samples = sample_after_iteration(curr_u);
+        for(auto &&sample : samples) {
+            std::cout << curr_u << ' ' << sample << std::endl;
+        }
+    }
+}
+
+int main() {
+    print_points();
+}
+

run.sh

+g++ generate-points.cc -O3 -o generate-points && ./generate-points | tee points.log && python draw.py