If you use %pylab inline
you can (on a new line) insert the following command:
%pylab inline
pylab.rcParams['figure.figsize'] = (10, 6)
This will set all figures in your document (unless otherwise specified) to be of the size (10, 6)
, where the first entry is the width and the second is the height.
See this SO post for more details. https://stackoverflow.com/a/17231361/1419668