How do you change the size of figures drawn with Matplotlib?

figure tells you the call signature:

from matplotlib.pyplot import figurefigure(figsize=(8, 6), dpi=80)

figure(figsize=(1,1)) would create an inch-by-inch image, which would be 80-by-80 pixels unless you also give a different dpi argument.

If you've already got the figure created, you can quickly do this:

fig = matplotlib.pyplot.gcf()fig.set_size_inches(18.5, 10.5)fig.savefig('test2png.png', dpi=100)

To propagate the size change to an existing GUI window, add forward=True:

fig.set_size_inches(18.5, 10.5, forward=True)

Using plt.rcParams

There is also this workaround in case you want to change the size without using the figure environment. So in case you are using plt.plot() for example, you can set a tuple with width and height.

import matplotlib.pyplot as pltplt.rcParams["figure.figsize"] = (20,3)

This is very useful when you plot inline (e.g., with IPython Notebook). As asmaier noticed, it is preferable to not put this statement in the same cell of the imports statements.

To reset the global figure size back to default for subsequent plots:

plt.rcParams["figure.figsize"] = plt.rcParamsDefault["figure.figsize"]

Conversion to cm

The figsize tuple accepts inches, so if you want to set it in centimetres you have to divide them by 2.54. Have a look at this question.