按钮

构建一个简单的按钮GUI来修改正弦波。

下一个和上一个按钮小部件有助于以新频率显示波形。

按钮示例

  1. import numpy as np
  2. import matplotlib.pyplot as plt
  3. from matplotlib.widgets import Button
  5. freqs = np.arange(2, 20, 3)
  7. fig, ax = plt.subplots()
  8. plt.subplots_adjust(bottom=0.2)
  9. t = np.arange(0.0, 1.0, 0.001)
  10. s = np.sin(2*np.pi*freqs[0]*t)
  11. l, = plt.plot(t, s, lw=2)
  14. class Index(object):
  15.     ind = 0
  17.     def next(self, event):
  18.         self.ind += 1
  19.         i = self.ind % len(freqs)
  20.         ydata = np.sin(2*np.pi*freqs[i]*t)
  21.         l.set_ydata(ydata)
  22.         plt.draw()
  24.     def prev(self, event):
  25.         self.ind -= 1
  26.         i = self.ind % len(freqs)
  27.         ydata = np.sin(2*np.pi*freqs[i]*t)
  28.         l.set_ydata(ydata)
  29.         plt.draw()
  31. callback = Index()
  32. axprev = plt.axes([0.7, 0.05, 0.1, 0.075])
  33. axnext = plt.axes([0.81, 0.05, 0.1, 0.075])
  34. bnext = Button(axnext, 'Next')
  35. bnext.on_clicked(callback.next)
  36. bprev = Button(axprev, 'Previous')
  37. bprev.on_clicked(callback.prev)
  39. plt.show()

下载这个示例