title in italic font in matplotlib isn't working

Question

import matplotlib.pyplot as plt
from textwrap import wrap

x_list = [11, 3, 6, 5]
label_list = ["red colour", "blue colour", "green colour", "back colour"]

title = "Some really really long long long title I really really need - and just can't - just can't - make it any - simply any - shorter - at all?"

newtitle = '\n'.join(wrap(title, width=50))  # wrap the long title so that it won't get cropped.

# here if I print `newtitle` first then "text below the main title" gets convert into italics
newtitle = "%s\n$%s$"%(newtitle, 'text\ below\ the\ main\ title') 
# but If I print `newtitle` after the secondary text it doesn't convert into italics
newtitle = "%s\n$%s$"%('text\ below\ the\ main\ title', newtitle)  # comment this line for 1st effect

plt.figure(figsize=(7,6), dpi=100)
plt.axis("equal")
plt.subplots_adjust(left=0.1, right=0.8, top=0.7)
plt.rc("font", size=10)
explode = [0.03, 0, 0, 0]

plt.pie(x_list, labels=label_list, explode=explode, autopct="%1.1f%%", startangle=90)
plt.title(newtitle, size=12)

plt.savefig('test.png')

So my main problem is -

secondary text come first in normal font and then main title(newtitle) come after this in italics/light font (looks pretty).

newtitle = "%s\n$%s$"%('text\ below\ the\ main\ title', newtitle)

Can we do it without using $ sign?

have you checked this: http://stackoverflow.com/a/4056853/832621 ? — Saullo G. P. Castro, Sep 26 '14 at 08:48
@SaulloCastro: yeah.. but its too much code. I wonder if this can be done smartly/shortly. — xyz, Sep 26 '14 at 08:49

CT Zhu · Accepted Answer · 2014-09-26T16:56:43.647

Is this the intended result?

enter image description here

It can be done in a quick and dirty way using mathtext, but you have to have $ flaking each lines, such as:

newtitle = '\n'.join(['$%s$'%item for item in wrap(title, width=50)]).replace(' ', '\ ')
newtitle = "%s\n%s"%('text\ below\ the\ main\ title', newtitle)

But I think a better looking way is to have these two titles separated. You can use suptitle for the upper one, or maybe just use text, either way you can then control their properties independently. e.g.:

plt.pie(x_list, labels=label_list, explode=explode, autopct="%1.1f%%", startangle=90)
plt.title('\n'.join(wrap(title, width=50)), size=12, style='italic')
plt.suptitle('some title', y=0.85, x=0.45) #y and x needed as you have adjusted the subplot size already.

enter image description here

title in italic font in matplotlib isn't working

1 Answers1