教你用Python matplotlib库制作简单的动画

import matplotlib.animation as ma
def update(number):
    pass

# 每隔30毫秒,执行一次update
ma.FuncAnimation(
    mp.gcf(),   # 作用域当前窗体
    update,     # 更新函数的函数名
    interval=30 # 每隔30毫秒,执行一次update
)  

"""
简单动画
1. 随机生成100个气泡.
2. 每个气泡拥有四个属性: position, size, growth, color
3. 把每个气泡绘制到窗口中.
4. 开启动画,在update函数中更新每个气泡的属性并重新绘制
"""
import numpy as np
import matplotlib.pyplot as mp
import matplotlib.animation as ma

n = 100
balls = np.zeros(n, dtype=[
		('position', float, 2), # 位置属性
		('size', float, 1),     # 大小属性
		('growth', float, 1),   # 生长速度
		('color', float, 4)])   # 颜色属性
# 初始化每个泡泡
# uniform: 从0到1取随机数,填充n行2列的数组
balls['position']=np.random.uniform(0,1,(n,2))
balls['size']=np.random.uniform(50,70,n)
balls['growth']=np.random.uniform(10,20,n)
balls['color']=np.random.uniform(0,1,(n,4))
# 绘制100个泡泡
mp.figure('Bubble', facecolor='lightgray')
mp.title('Bubble', fontsize=18)
mp.xticks([])
mp.yticks([])
sc = mp.scatter(balls['position'][:,0], 
	       balls['position'][:,1],
	       balls['size'], 
	       color=balls['color'])

# 启动动画
def update(number):
	balls['size'] += balls['growth']
	# 让某个泡泡破裂,从头开始执行
	boom_i = number % n
	balls[boom_i]['size'] = 60
	balls[boom_i]['position']= \
			np.random.uniform(0, 1, (1, 2))
	# 重新设置属性
	sc.set_sizes(balls['size'])
	sc.set_offsets(balls['position'])

anim = ma.FuncAnimation(
	mp.gcf(), update, interval=30)

mp.show()

"""
模拟心电图
"""
import numpy as np
import matplotlib.pyplot as mp
import matplotlib.animation as ma

mp.figure('Signal', facecolor='lightgray')
mp.title('Signal', fontsize=16)
mp.xlim(0, 10)
mp.ylim(-3, 3)
mp.grid(linestyle=':')
pl = mp.plot([],[], color='dodgerblue',
		label='Signal')[0]
# 启动动画
def update(data):
	t, v = data
	x, y = pl.get_data()  #x y: ndarray数组
	x = np.append(x, t)
	y = np.append(y, v)
	# 重新绘制图像
	pl.set_data(x, y)
	# 移动坐标轴
	if x[-1]>5:
		mp.xlim(x[-1]-5, x[-1]+5)

x = 0
def generator():
	global x
	y = np.sin(2 * np.pi * x) * \
		np.exp(np.sin(0.2 * np.pi * x))
	yield (x, y)
	x += 0.05

anim = ma.FuncAnimation(mp.gcf(), 
	update, generator, interval=30)
mp.show()