Scrolling back and forth on a matplotlib chart

Question

My code creates several graphs from the data using matplotib, and I would like to be able to scroll forward and backward through them in a live demo (perhaps by pressing the back and forth keys or using the mouse). Currently, I have to save each as an image separately, and then use a separate image viewer to scroll through them. Is there a way to do this completely from within python?

Answer 1

An easy way to achieve this is to store the arrays x and y in the tuple list, and then use a handler event that selects the next (x, y) pair to be constructed:

import numpy as np import matplotlib.pyplot as plt # define your x and y arrays to be plotted t = np.linspace(start=0, stop=2*np.pi, num=100) y1 = np.cos(t) y2 = np.sin(t) y3 = np.tan(t) plots = [(t,y1), (t,y2), (t,y3)] # now the real code :) curr_pos = 0 def key_event(e): global curr_pos if e.key == "right": curr_pos = curr_pos + 1 elif e.key == "left": curr_pos = curr_pos - 1 else: return curr_pos = curr_pos % len(plots) ax.cla() ax.plot(plots[curr_pos][0], plots[curr_pos][1]) fig.canvas.draw() fig = plt.figure() fig.canvas.mpl_connect('key_press_event', key_event) ax = fig.add_subplot(111) ax.plot(t,y1) plt.show() 

In this code, I select the right and left arrows for iteration, but you can change them.