python中的极圈动画

Question

这是我的 python 文件，用于模拟一个圆的振荡动力学，该圆永久地扩展和收缩：

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

fig = plt.figure()
ax = plt.axes(xlim=(0, 2), ylim=(-2, 2))
line, = ax.plot([], [], lw=2)

def init():
    line.set_data([], [])
    return line,

def animate(i):
    theta = np.linspace(0, 2 * np.pi, 100)
    r = np.sqrt(np.abs(np.sin(0.1 * i)))
    x = r * np.cos(theta) + 1
    y = r * np.sin(theta)
    line.set_data(x, y)
    return line,

anim = animation.FuncAnimation(fig, animate, init_func=init, frames=200, interval=20, blit=True)

plt.show()

但是参数定义有缺陷，结果不是动画圆，而是省略号。

我该如何解决这个问题？

Answer 1

尝试添加plt.gca().set_aspect('equal', adjustable='box') 并修改您的ylim，如下所示：

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

fig = plt.figure()
ax = plt.axes(xlim=(0, 2), ylim=(-1, 1))
line, = ax.plot([], [], lw=2)

def init():
    line.set_data([], [])
    return line,

def animate(i):
    theta = np.linspace(0, 2 * np.pi, 100)
    r = np.sqrt(np.abs(np.sin(0.1 * i)))
    x = r * np.cos(theta) + 1
    y = r * np.sin(theta)
    line.set_data(x, y)
    return line,

anim = animation.FuncAnimation(fig, animate, init_func=init, frames=200, interval=20, blit=True)

plt.gca().set_aspect('equal', adjustable='box')
plt.show()

这将显示如下：

Answer 2

您的坐标轴长度不同（边界框），试试这个：

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

fig = plt.figure()
ax = plt.axes(xlim=(-2, 2), ylim=(-2, 2))
line, = ax.plot([], [], lw=2)

def init():
    line.set_data([], [])
    return line,

def animate(i):
    theta = np.linspace(0, 2 * np.pi, 100)
    r = 2*np.sqrt(np.abs(np.sin(0.1 * i)))
    x = r * np.cos(theta)
    y = r * np.sin(theta)
    line.set_data(x, y)
    return line,

anim = animation.FuncAnimation(fig, animate, init_func=init, frames=200, interval=20, blit=True)

plt.show()