Python&数学基礎
モンテカルロ法
プログラム（Python 3.10.4）
import matplotlib.pyplot as plt
import matplotlib.patches as patches
import numpy as np
import pandas as pd
def montecarlo():
fig, ax = plt.subplots(figsize = (4, 4))
ucircle = patches.Circle(xy=(0.0,0.0), radius=1.0, edgecolor='black', fill=False)
ax.add_patch(ucircle)
num = 500
inCircle = 0
x = np.random.uniform(-1, 1, num)
y = np.random.uniform(-1, 1, num)
x_green = [x for x, y in zip(x, y) if x**2+y**2 <= 1]
y_green = [y for x, y in zip(x, y) if x**2+y**2 <= 1]
x_red = [x for x, y in zip(x, y) if x**2+y**2 > 1]
y_red = [y for x, y in zip(x, y) if x**2+y**2 > 1]
inCircle = len(x_green)
plt.scatter(x_green, y_green, marker='o', color='green')
plt.scatter(x_red, y_red, marker='x', color='red')
pi = 4 * inCircle / num
plt.title('MonteCarlo'+' N='+str(num)+' pi='+str(pi))
plt.show()