Martplotlib滑塊不起作用

Question

我需要製作一些具有多個參數的圖，我選擇使它與matplotlib滑塊更具互動性。對於我在實際工作之前的一些練習，我試圖讓它變得相當簡單，但我的滑塊不起作用。這是代碼，這是從here的啓發。

代碼：

import matplotlib 
import matplotlib.pyplot as plt 
import matplotlib.widgets as mw 
from scipy import stats 


mu = 1 
sigma = 3 

a = 2 
b = 3 
axis_color = 'lightgoldenrodyellow' 


x = [i for i in range(-100,100,1)] 

normal_pdf = stats.norm.pdf(x, mu, sigma) 
a_normal_pdf = [i*a for i in normal_pdf] 
ab_normal_pdf = [i*b*a for i in normal_pdf] 


fig = plt.figure() 

ax1 = fig.add_subplot(221) 
ax2 = fig.add_subplot(222) 
ax3 = fig.add_subplot(223) 
ax4 = fig.add_subplot(224) 
ax4.axis('off') 
#sliders 
a_slider_ax = fig.add_axes([0.6, 0.25, 0.25, 0.03], axisbg=axis_color) 
a_slider = mw.Slider(a_slider_ax, 'a', 1, 100, valinit = a) 
b_slider_ax = fig.add_axes([0.6, 0.4, 0.25, .03], axisbg = axis_color) 
b_slider = mw.Slider(b_slider_ax, 'b', 1, 100, valinit = b) 
#function for sliders 
def sliders_on_change(val): 
    a_normal_pdf.set_ydata([x*a_slider for x in normal_pdf]) 
    ab_normal_pdf.set_ydata([x*a_slider*b_slider for x in normal_pdf]) 
    fig.canvas.draw_idle() 
a_slider.on_changed(sliders_on_change) 
b_slider.on_changed(sliders_on_change) 


ax1.plot(x, normal_pdf, 'r-') 
ax2.plot(x, a_normal_pdf, 'bo') 
ax3.plot(x, ab_normal_pdf, 'g*') 

plt.show() 

我不完全瞭解滑塊應該工作，所以它也許問題，而不是閒置問題爲here，因爲我的Spyder和jupyter試了一下也沒有什麼區別。我可以移動滑塊，但我不能更改a_normal_pdf和ab_normal_pdf。

Answer 1

你在你的代碼的兩個問題：使用滑塊對象a_slider

1. 到位滑塊的當前值的a_slider.val

2. set_ydata改變Line2D劇情對象的y數據的方法（我在一個變量p1保存它能夠對其進行修改）

修改後的代碼（希望這有助於）

import matplotlib 
import matplotlib.pyplot as plt 
import matplotlib.widgets as mw 
from scipy import stats 


mu = 1 
sigma = 3 

a = 2 
b = 3 
axis_color = 'lightgoldenrodyellow' 


x = [i for i in range(-100,100,1)] 

normal_pdf = stats.norm.pdf(x, mu, sigma) 
a_normal_pdf = [i*a for i in normal_pdf] 
ab_normal_pdf = [i*b*a for i in normal_pdf] 


fig = plt.figure() 

ax1 = fig.add_subplot(221) 
ax2 = fig.add_subplot(222) 
ax3 = fig.add_subplot(223) 
ax4 = fig.add_subplot(224) 
ax4.axis('off') 
#sliders 
a_slider_ax = fig.add_axes([0.6, 0.25, 0.25, 0.03], axisbg=axis_color) 
a_slider = mw.Slider(a_slider_ax, 'a', 1, 100, valinit = a) 
b_slider_ax = fig.add_axes([0.6, 0.4, 0.25, .03], axisbg = axis_color) 
b_slider = mw.Slider(b_slider_ax, 'b', 1, 100, valinit = b) 
#function for sliders 
def sliders_on_change(val): 
    p1.set_ydata([x*a_slider.val for x in normal_pdf]) 
    p2.set_ydata([x*a_slider.val*b_slider.val for x in normal_pdf]) 
    fig.canvas.draw_idle() 

a_slider.on_changed(sliders_on_change) 
b_slider.on_changed(sliders_on_change) 


p1,=ax1.plot(x, normal_pdf, 'r-') 
p2,=ax2.plot(x, a_normal_pdf, 'bo') 
p3,=ax3.plot(x, ab_normal_pdf, 'g*') 

plt.show()