I wanted to use the matplotlib slider as seen in an example from a previous question (below) inside a GUI window (such as TkInter etc). But, in a non-global context, the variables for the plot ("spos, fig, ax") are not defined. My understanding is that because update is used as a callback function, one can't or shouldn't pass arguments.
If so, how can a plot be updated without global variables? or
How can I obtain the slider position outside the callback function?
import numpy as np import matplotlib.pyplot as plt from matplotlib.widgets import Slider fig, ax = plt.subplots() plt.subplots_adjust(bottom=0.25) t = np.arange(0.0, 100.0, 0.1) s = np.sin(2*np.pi*t) l, = plt.plot(t,s) plt.axis([0, 10, -1, 1]) axcolor = 'lightgoldenrodyellow' axpos = plt.axes([0.2, 0.1, 0.65, 0.03], axisbg=axcolor) spos = Slider(axpos, 'Pos', 0.1, 90.0) def update(val): pos = spos.val ax.axis([pos,pos+10,-1,1]) fig.canvas.draw_idle() spos.on_changed(update) plt.show() Related:
1) Another related question seems to cover this topic but does not seem to address how the position of the slider is obtained.
2) A similar question was asked and solved with Slider.set_val(). It seems in my case I would need Slider.get_val() instead.
