Choosing which figures to show on-screen and which to save to a file using Python's matplotlib

Question

I'd like to create different figures in Python using matplotlib.pyplot. I'd then like to save some of them to a file, while others should be shown on-screen using the show() command.

However, show() displays all created figures. I can avoid this by calling close() after creating the plots which I don't want to show on-screen, like in the following code:

import matplotlib.pyplot as plt

y1 = [4, 2, 7, 3]
y2 = [-7, 0, -1, -3]

plt.figure()
plt.plot(y1)
plt.savefig('figure1.png')
plt.close()

plt.figure()
plt.plot(y2)

plt.show()
plt.close('all')

This saves the first figure and shows the second one. However, I get an error message:

can't invoke "event" command: application has been destroyed while executing

Is it possible to select in a more elegant way which figures to show?

Also, is the first figure() command superfluous? It doesn't seem to make a different whether I give it or not.

Many thanks in advance.

Answer 1

The better way is to use plt.clf() instead of plt.close(). Moreover plt.figure() creates a new graph while you can just clear previous one with plt.clf():

import matplotlib.pyplot as plt

y1 = [4, 2, 7, 3]
y2 = [-7, 0, -1, -3]

plt.figure()
plt.plot(y1)
plt.savefig('figure1.png')
plt.clf()

plt.plot(y2)

plt.show()
plt.clf()

This code will not generate errors or warnings such can't invoke "event" command...