Python中关于动画的简单问题答案

【问题标题】：Simple question about animation in PythonPython中关于动画的简单问题
【发布时间】：2021-11-02 19:11:42
【问题描述】：

有一个简单的代码可以根据一些简单的规则画线。

它可以工作，但我想通过更改一个参数theta_time 来动画它。

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

List_1 = [6,4,2,1]
List_2 = [0,0,0,0]
List_3 = [6,4,3,2]

fig, ax = plt.subplots()

C_x = 0
C_y = 0
cx = [0]
cy = [0]

theta_time = 1  #I want to update this value from 0 to 10

for freq,amp,phase in zip(List_3,List_1, List_2):

    C_x += amp*np.cos(freq * theta_time + np.deg2rad(phase))
    C_y += amp*np.sin(freq * theta_time + np.deg2rad(phase))
    cx.append(C_x)
    cy.append(C_y)

plt.scatter(cx,cy)
plt.plot(cx, cy, '.r-',linewidth=1)    
plt.show()

我尝试将以下代码添加到动画中，但它不起作用

def animations(theta_time):
    for freq,amp, phase in zip(List_3,List_1, List_2):

    C_x += amp*np.cos(freq * theta_time + np.deg2rad(phase))
    C_y += amp*np.sin(freq * theta_time + np.deg2rad(phase))
    cx.append(C_x)
    cy.append(C_y)

ani = animation.FuncAnimation(
   fig, animations,frames=np.arange(0,1,0.01),interval=10, blit=False)

【问题讨论】：

标签： python numpy matplotlib animation visualization

【解决方案1】：

您应该在animation 函数中移动所有计算和绘图线。在此函数中要做的第一件事是用ax.cla() 擦除先前的绘图（否则新帧将与先前的帧重叠）。我建议在animation 中添加ax.set_xlim 和ax.set_ylim，以固定每帧中的轴限制并避免在帧之间重新调整轴的大小。我还添加了一个带有当前 theta_time 值的标题，如果需要，可以将其删除。

完整代码

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


List_1 = [6,4,2,1]
List_2 = [0,0,0,0]
List_3 = [6,4,3,2]


def animate(theta_time):

    ax.cla()

    C_x = 0
    C_y = 0
    cx = [0]
    cy = [0]

    for freq,amp,phase in zip(List_3,List_1, List_2):

        C_x += amp*np.cos(freq * theta_time + np.deg2rad(phase))
        C_y += amp*np.sin(freq * theta_time + np.deg2rad(phase))
        cx.append(C_x)
        cy.append(C_y)

    ax.scatter(cx,cy)
    ax.plot(cx, cy, '.r-',linewidth=1)

    ax.set_xlim(-15, 15)
    ax.set_ylim(-15, 15)
    ax.set_title(r'$\theta_{time} = $' + str(theta_time))


fig, ax = plt.subplots(figsize = (5, 5))

ani = FuncAnimation(fig = fig, func = animate, interval = 500, frames = 10)

plt.show()

【讨论】：