Question

早上好！

问题说明： 我想制作一个多边形，该多边形是我从数组中接收到的值（在我的简单示例中，它是一个移动的正方形）。我想让Polygon的x和y值保持可变。不用担心多边形会发生什么运动。这只是一个例子。希望像在“ animation to translate polygon using matplotlib”解决方案中一样使用“ set_xy（）”。

目标->在每个动画帧中，我想从数组（P1x，P1y，P2x，P2y，...）中加载多边形值并更新图形。

问题： 在我的代码中，使用补丁仍存在问题。我正在尝试使用索引i更新Polygon值。我必须如何定义补丁？是否必须通过动画调用来完成？

import matplotlib.pyplot as plt
import numpy as np
import matplotlib.animation as animation
import matplotlib.patches as patches

fig = plt.figure()
ax = fig.add_subplot(111)
ax.set_xlim(-10,10)
ax.set_ylim(-10,10)

P1x=[0.0,0.5,1.0,1.5,2.0,2.5,3.0]
P1y=[0.0,0.0,0.0,0.0,0.0,0.0,0.0]
P2x=[1.0,1.5,2.0,2.5,3.0,3.5,4.0]
P2y=[0.0,0.0,0.0,0.0,0.0,0.0,0.0]
P3x=[1.0,1.5,2.0,2.5,3.0,3.5,4.0]
P3y=[1.0,1.0,1.0,1.0,1.0,1.0,1.0]
P4x=[0.0,0.5,1.0,1.5,2.0,2.5,3.0]
P4y=[1.0,1.0,1.0,1.0,1.0,1.0,1.0]

def init():
    return patch,

def animate(i):
    v = np.array([
                [P1x[i],  P1y[i]],  
                [P2x[i],  P2y[i]],  
                [P3x[i],  P3y[i]],
                [P4x[i],  P4y[i]]
                ])
    patch=patches.Polygon(v,closed=True, fc='r', ec='r')

    return patch,

ani = animation.FuncAnimation(fig, animate, np.arange(1, 5), init_func=init,
                              interval=1000, blit=True)
plt.show()

非常感谢您的帮助！

Answer 1

是的，您需要首先创建多边形并将其添加到轴。在动画功能内部，您可以使用面片的patch.set_xy()方法来更新多边形的顶点。

import matplotlib.pyplot as plt
import numpy as np
import matplotlib.animation as animation
import matplotlib.patches as patches

fig = plt.figure()
ax = fig.add_subplot(111)
ax.set_xlim(-10,10)
ax.set_ylim(-10,10)

P1x=[0.0,0.5,1.0,1.5,2.0,2.5,3.0]
P1y=[0.0,0.0,0.0,0.0,0.0,0.0,0.0]
P2x=[1.0,1.5,2.0,2.5,3.0,3.5,4.0]
P2y=[0.0,0.0,0.0,0.0,0.0,0.0,0.0]
P3x=[1.0,1.5,2.0,2.5,3.0,3.5,4.0]
P3y=[1.0,1.0,1.0,1.0,1.0,1.0,1.0]
P4x=[0.0,0.5,1.0,1.5,2.0,2.5,3.0]
P4y=[1.0,1.0,1.0,1.0,1.0,1.0,1.0]

P = np.concatenate((np.array([P1x, P2x, P3x, P4x]).reshape(4,1,len(P1x)),
                    np.array([P1y, P2y, P3y, P4y]).reshape(4,1,len(P1x))), axis=1)

patch = patches.Polygon(P[:,:,0],closed=True, fc='r', ec='r')
ax.add_patch(patch)

def init():
    return patch,

def animate(i):
    patch.set_xy(P[:,:,i])
    return patch,

ani = animation.FuncAnimation(fig, animate, np.arange(P.shape[2]), init_func=init,
                              interval=1000, blit=True)
plt.show()

如何使用Python和Matplotlib

1 个答案: