- Matplotlib version: 2.0.0b1+117.gb2b37fb, Python version: 3.5.2 and Platform: Ubuntu 16.04 64bit
- Matplotlib from source and Python is shipped with system
- The following code is an example has the issue. It's from matplotlib example 'buttons.py', but modified with keyboard event supporting ( I only inserted lines from "istep=0" to "fig.canvas.mpl_connect" ). The problem is that after I zoomed in the figure with the zoom tool of matplotlib, the zooming level maintained when I pressed the next and previous button and right key, but lost when I pressed left key. I'm not sure whether this issue comes from my code or it is just a feature not supported by matplotlib.
import numpy as np
import matplotlib.pyplot as plt
from matplotlib.widgets import Button
freqs = np.arange(2, 20, 3)
fig, ax = plt.subplots()
plt.subplots_adjust(bottom=0.2)
t = np.arange(0.0, 1.0, 0.001)
s = np.sin(2*np.pi*freqs[0]*t)
l, = plt.plot(t, s, lw=2)
class Index(object):
ind = 0
def next(self, event):
self.ind += 1
i = self.ind % len(freqs)
ydata = np.sin(2*np.pi*freqs[i]*t)
l.set_ydata(ydata)
plt.draw()
def prev(self, event):
self.ind -= 1
i = self.ind % len(freqs)
ydata = np.sin(2*np.pi*freqs[i]*t)
l.set_ydata(ydata)
plt.draw()
istep=0
def on_keyboard(event):
global istep
global l
if event.key == 'right':
istep+=1
elif event.key == 'left':
istep-=1
ydata = np.sin(2*np.pi*freqs[istep%len(freqs)]*t)
l.remove()
l,=ax.plot(t,ydata)
fig.canvas.draw()
fig.canvas.mpl_connect('key_press_event', on_keyboard)
callback = Index()
axprev = plt.axes([0.7, 0.05, 0.1, 0.075])
axnext = plt.axes([0.81, 0.05, 0.1, 0.075])
bnext = Button(axnext, 'Next')
bnext.on_clicked(callback.next)
bprev = Button(axprev, 'Previous')
bprev.on_clicked(callback.prev)
plt.show()
