如何繪製在圓內移動的動畫點？

Question

我正在嘗試編寫一個函數來生成在圓內移動的點。我已經有了一個用matpltolib動畫繪製動畫點的功能（感謝Tony Babarino），但是我很難編寫強制點的部分留在圓圈中

這就是運動起作用的部分

import numpy as np 
from matplotlib import pyplot as plt 
from matplotlib import animation 

# Initializing number of dots 
N = 25 


# Creating dot class 
class dot(object): 
    def __init__(self): 
     self.x = 10 * np.random.random_sample() 
     self.y = 10 * np.random.random_sample() 
     self.velx = self.generate_new_vel() 
     self.vely = self.generate_new_vel() 

    def generate_new_vel(self): 
     return (np.random.random_sample() - 0.5)/5 

    def move(self) : 
      if np.random.random_sample() < 0.95: 
       self.x = self.x + self.velx 
       self.y = self.y + self.vely 
      else: 
       self.velx = self.generate_new_vel() 
       self.vely = self.generate_new_vel() 
       self.x = self.x + self.velx 
       self.y = self.y + self.vely 

# Initializing dots 
dots = [dot() for i in range(N)] 

# First set up the figure, the axis, and the plot element we want to animate 
fig = plt.figure() 
ax = plt.axes(xlim=(0, 10), ylim=(0, 10)) 
d, = ax.plot([dot.x for dot in dots], 
      [dot.y for dot in dots], 'ro', markersize=3) 
circle = plt.Circle((5, 5), 1, color='b', fill=False) 
ax.add_artist(circle) 


# animation function. This is called sequentially 
def animate(i): 
    for dot in dots: 
     dot.move() 
    d.set_data([dot.x for dot in dots], 
       [dot.y for dot in dots]) 
    return d, 

# call the animator. 
anim = animation.FuncAnimation(fig, animate, frames=200, interval=20) 

plt.show() 

我想補充說，強制點在圈內 我想圓的邊界要像圍牆，該點不能跨越到SATY的一部分，以完善的功能舉動

我知道如何檢測一個點c拋出線路，但我不知道該怎麼做。

非常感謝您的幫助

Answer 1

我改變了代碼，這樣你就不必vibarting和逃避圓的問題。進入圓圈的每個點都不會逃脫（點的起點可能在圓外），也不會在圓的邊緣振動。 進口numpy的是NP 從matplotlib進口pyplot從matplotlib進口動畫

# Initializing number of dots 
N = 25 
XC = 5 
YC = 5 
R = 1 
R_SQR = R **2 

# Creating dot class 
class dot(object): 
    def __init__(self, ind): 
     self.x = 10 * np.random.random_sample() 
     self.y = 10 * np.random.random_sample() 
     self.velx = self.generate_new_vel() 
     self.vely = self.generate_new_vel() 
     self.in_circle = not self.calc_out_of_circle() 

    def generate_new_vel(self): 
     return (np.random.random_sample() - 0.5)/5 

    def move(self) : 
     if np.random.random_sample() < 0.95: 
      self.check_out_of_circle() 
      self.x += self.velx 
      self.y += self.vely 
     else: 
      self.velx = self.generate_new_vel() 
      self.vely = self.generate_new_vel() 
      self.check_out_of_circle() 
      self.x += self.velx 
      self.y += self.vely 
     self.check_inside_circle() 

    def calc_out_of_circle_with_params(self, x, y): 
     return (x - XC) ** 2 + (y - YC) ** 2 >= R_SQR ** 2 

    def calc_out_of_circle(self): 
     return self.calc_out_of_circle_with_params(self.x, self.y) 

    def check_out_of_circle(self): 
     if self.in_circle and self.calc_out_of_circle_with_params(self.x + self.velx, self.y + self.vely): 
      self.velx = -self.velx 
      self.vely = -self.vely 

    def check_inside_circle(self): 
     if not self.calc_out_of_circle(): 
      self.in_circle = True 


# Initializing dots 
dots = [dot(i) for i in range(N)] 

# First set up the figure, the axis, and the plot element we want to animate 
fig = plt.figure() 
ax = plt.axes(xlim=(0, 10), ylim=(0, 10)) 
d, = ax.plot([dot.x for dot in dots], 
      [dot.y for dot in dots], 'ro', markersize=3) 
circle = plt.Circle((XC, YC), R, color='b', fill=False) 
ax.add_artist(circle) 


# animation function. This is called sequentially 
def animate(i): 
    for dot in dots: 
     dot.move() 
    d.set_data([dot.x for dot in dots], 
       [dot.y for dot in dots]) 
    return d, 

# call the animator. 
anim = animation.FuncAnimation(fig, animate, frames=200, interval=20) 
# plt.axis('equal') 
plt.show()