How to change all text sizes in figure when using python matplotlib?

Question

I saw a long time ago a function that changed all text sizes to same in matplotlib. Now I can't find it anywhere. It was a simple one (or two) liner like:

for item in pylab.gca(): item.getLabel().setSize(10)

How should I do the above? The above is just pseudocode, but the idea is to change x and y labels, legends, titles, everything.

EDIT : ...inside one figure (object). I want the text size to be dependent on the figure width. The global font.size changes this for all figures? and I think it cannot be applied dynamically (settings are read only before the figure is created)?

EDIT 2 : I tested the font.size = 22 method. It has some weird behavior if you run it after eg legend(). The text vertical spaces are not updated. So, it should be something like getText().setTextSize().

Answer 1

Instead of changing the font size you could change the figsize (the font size stays the same):

# figsize = (8,6)
figsize = (4,3) # same ratio, bigger text
fig,(ax) = plt.subplots(1, 1, figsize=figsize)

EDIT (for completeness): The size of the pixels (on screen) is controlled by the dpi setting which is settable ie by Figure.set_dpi( val ).

EDIT 2 : I don't know how (and if) you can control the exact pixel height. I did some tests though:

#! /usr/bin/env python

import matplotlib
import matplotlib.pyplot as plt
import numpy as np

x = np.arange(0, 2*np.pi, 0.1)
y = np.sin(x)

matplotlib.rcParams.update({'font.size': 10})
fig,(ax) = plt.subplots(1, 1, figsize=(10,10))
plt.plot(x,y)
plt.savefig('test.png', dpi=300)

# font-size, figsize, dpi => pixel-height
# 10, 20x20, 100 => 10
# 10, 20x20, 200 => 21
# 10, 10x10, 100 => 10
# 10, 10x10, 200 => 21
# 10, 10x10, 300 => 34

Also note that there are probably effects on the pixel height due to anti-aliasing.