在matplotlib中使用滑块不更新子图

如何解决在matplotlib中使用滑块不更新子图

我不确定滑块出现了什么问题。一旦修改了滑块值，它就不会更新。我被困了很长时间，任何线索都会有所帮助。预先感谢！

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.widgets import Slider,Button,RadioButtons
import matplotlib.animation as animation

plt.cla()

n = 1000
x1 = np.random.normal(5,1,n)
x2 = np.random.gamma(2,1.5,n)
x3 = np.random.exponential(2,n)
x4 = np.random.uniform(0,10,n)

fig,((ax1,ax2),(ax3,ax4)) = plt.subplots(2,2,sharey=True,sharex = True)
plt.axis([0,600])
axs = [ax1,ax2,ax3,ax4]

ax1.hist(x1,density=False,bins=10,alpha=0.5)
ax2.hist(x2,alpha=0.5)
ax3.hist(x3,alpha=0.5)
ax4.hist(x4,alpha=0.5)

axcolor = 'lightgoldenrodyellow'
axfreq = plt.axes([.2,.01,.65,.02],facecolor=axcolor)
sample_slider = DiscreteSlider(axfreq,'Sample Size \n (100-1000)',100,1000,valinit=1000)

def update(val):
    n = sample_slider.val
    print(n)
    
    plt.annotate('n = {}'.format(n),[9,15])
    
    ax1.cla()
    ax2.cla()
    ax3.cla()
    ax4.cla()
    
    x_1 = np.random.normal(5,n)
    x_2 = np.random.gamma(2,n)
    x_3 = np.random.exponential(2,n)
    x_4 = np.random.uniform(0,n)
    
    plt.axis([0,500])
    ax1.hist(x_4,alpha=0.5)
    ax2.hist(x_3,alpha=0.5)
    ax3.hist(x_2,alpha=0.5)
    ax4.hist(x_1,alpha=0.5)
    
    fig.canvas.draw_idle()
           
sample_slider.on_changed(update)

plt.show()

离散滑块-我正在上课

DiscreteSlider（Slider）类： “”“具有离散步骤的matplotlib滑块小部件。”“” def init （自身，* args，** kwargs）： “”“与Slider相同。初始化，但“增量” kwarg除外。 “ increment”（增量）指定将使滑块离散化的步长 至。””” self.inc = kwargs.pop（'increment'，50） 滑块。 init （自身，* args，** kwargs） self.val = 1

def set_val(self,val):
    discrete_val = int(val / self.inc) * self.inc
    # We can't just call Slider.set_val(self,discrete_val),because this 
    # will prevent the slider from updating properly (it will get stuck at
    # the first step and not "slide"). Instead,we'll keep track of the
    # the continuous value as self.val and pass in the discrete value to
    # everything else.
    xy = self.poly.xy
    xy[2] = discrete_val,1
    xy[3] = discrete_val,0
    self.poly.xy = xy
    self.valtext.set_text(self.valfmt % discrete_val)
    if self.drawon: 
        self.ax.figure.canvas.draw()
    self.val = val
    if not self.eventson: 
        return
    for cid,func in self.observers.items():
        func(discrete_val)