Repository navigation
Feature request: set mathtext fonts via the object oriented API #6518
Description
As far as I can see (and according to the documentation), the only way to set the font of mathtext snippets in plots is via the mathtext.fontset rcparam.
It would be nice if there were some way to control the fonts used for mathtext rendering without messing with the rcparams system. Maybe the font could be chosen based on the FontProperties instance associated with the Text object? To make a concrete example, it would be nice if the y label for this plot were rendered using a serif font, like the rest of the plot.
import numpy as np
from matplotlib import pyplot as plt
from matplotlib.font_manager import FontProperties
fig, ax = plt.subplots()
fp = FontProperties(**{'family': 'stixgeneral'})
im = ax.imshow(np.random.random((800, 800)))
cb = fig.colorbar(im)
cbax = cb.ax
ax.set_xlabel('x label')
ax.set_ylabel(r'$\rm{y\ label}$')
cb.set_label('colorbar label')
labels = ax.xaxis.get_ticklabels() + ax.yaxis.get_ticklabels()
labels += cbax.yaxis.get_ticklabels()
labels += [ax.xaxis.label, ax.yaxis.label, cbax.yaxis.label]
for label in labels:
label.set_fontproperties(fp)
plt.savefig('test.png')For additional context, see #6514 and my message to the matplotlib-devel mailing list: https://mail.python.org/pipermail/matplotlib-devel/2016-May/000454.html
Activity
zblz commentedon Jun 1, 2016
Can this be achieved with an
rc_contextwithouth touching user rcparams?I agree it would be nice for a way to set both text and mathtext fonts as a group so they are consistent, and currently it is not completely obvious.with mpl.rc_context(fname='mpl.rc', rc={'text.usetex': True}):
edit: nevermind, I saw you already mentioned the context manager in the email.
ngoldbaum commentedon Jun 1, 2016
While it's true that this issue can be dealt with using a context manager (ping @mdboom and @WeatherGod, let's move discussion to this issue since it has a clearer call for action), I think that's less useful than being able to programmatically customize fonts using the
FontPropertiesinterface. Keep in mind that I'm thinking in the context of yt, which has a several thousand line wrapper around matplotlib, so saying "use the context manager" is more complex for me since the plotting code is spread out over several modules (since I make use of inheritance to avoid code duplication) and many different functions.Here's a couple reasons to justify why I want something besides the context manager approach:
mdboom commentedon Jun 1, 2016
The tricky bit here is that math rendering requires a particular set of fonts that work together (the "fontset") rather than a single font. There are only a very small set of such fontsets supported. So we'd need to add a new property to
FontPropertyto set the fontset and ignore all others. Not really an ideal API either.ngoldbaum commentedon Jun 1, 2016
That actually sounds nice to me - I could do:
fp = FontProperties(**{'family': 'stixgeneral', 'mathtext-fontset': 'cmr'})
And non-mathtext text will use 'stixgeneral', while mathtext uses computer modern.
WeatherGod commentedon Jun 1, 2016
I'll be +1 to that idea, but I get the point that it isn't ideal. As a
user, I say "use this font", and that font doesn't get used... I would be
rather surprised. It isn't immediately obvious that I would need to specify
two parameters to set my fonts. The font-handling system is probably due
for an overhaul soon, I think.
On Wed, Jun 1, 2016 at 1:28 PM, ngoldbaum notifications@github.com wrote:
zblz commentedon Jun 2, 2016
A possible alternative would be to set
mathtext.fontsetby default to None, and write some logic that selects the fontset depending on the FontProperties of the surrounding text, trying to get as good a match as possible. Ifmathtext.fontsetis specified, then we go with that no matter the FontProperties. I imagine that this would be closer to most user's expected behaviour.However, in the case specified by @ngoldbaum (
'family': 'stixgeneral') the fontset chosen would probably have to be stix rather than cmr...efiring commentedon Jun 2, 2016
On 2016/06/01 10:51 PM, Victor Zabalza wrote:
Looking at surrounding text? That sounds much too complicated and magical.
anntzer commentedon May 23, 2021
Closed by #18145.