Latex font in matplotlib - Script-r - python

In matplotlib, one can easily use latex script to label axes, or write legends or any other text. But is there a way to use new fonts such as 'script-r' in matplotlib? In the following code, I am labelling the axes using latex fonts.
import numpy as np
import matplotlib.pyplot as plt
tmax=10
h=0.01
number_of_realizations=6
for n in range(number_of_realizations):
xpos1=0
xvel1=0
xlist=[]
tlist=[]
t=0
while t<tmax:
xlist.append(xpos1)
tlist.append(t)
xvel1=np.random.normal(loc=0.0, scale=1.0, size=None)
xpos2=xpos1+(h**0.5)*xvel1 # update position at time t
xpos1=xpos2
t=t+h
plt.plot(tlist, xlist)
plt.xlabel(r'$ t$', fontsize=50)
plt.ylabel(r'$r$', fontsize=50)
plt.title('Brownian motion', fontsize=20)
plt.show()
It produces the following figure
But I want 'script-r' in place of normal 'r'.
In latex one has to add the following lines in preamble to render 'script-r'
\DeclareFontFamily{T1}{calligra}{}
\DeclareFontShape{T1}{calligra}{m}{n}{<->s*[2.2]callig15}{}
\DeclareRobustCommand{\sr}{%
\mspace{-2mu}%
\text{\usefont{T1}{calligra}{m}{n}r\/}%
\mspace{2mu}%
}
I don't understand how to do this in matplotlib. Any help is appreciated.

Matplotlib uses it's own hand-rolled (pure Python) implementation of TeX to do all of the math text stuff, so you absolutely cannot assume that what works in standard LaTeX will work with Matplotlib. That being said, here's how you do it:
Install the calligra font so that Matplotlib can see it, then rebuild the font cache.
Lots of other threads deal with how to do this, I'm not going to go into detail, but here's some reference:
Use a font installed in a random spot on your filesystem.
How to install a new font into the Matplotlib managed font cache.
List all fonts currently known to your install of Matplotlib.
Replace one of Matplotlib's TeX font families with your font of choice.
Here's a function I wrote a while ago that reliably does that:
import matplotlib
def setMathtextFont(fontName='Helvetica', texFontFamilies=None):
texFontFamilies = ['it','rm','tt','bf','cal','sf'] if texFontFamilies is None else texFontFamilies
matplotlib.rcParams.update({'mathtext.fontset': 'custom'})
for texFontFamily in texFontFamilies:
matplotlib.rcParams.update({('mathtext.%s' % texFontFamily): fontName})
For you, a good way to use the function would be to replace the font used by \mathcal with calligra:
setMathtextFont('calligra', ['cal'])
Label your plots, for example, r'$\mathcal{foo}$', and the contents of the \math<whatever> macro should show up in the desired font.
Here's how you'd change your label-making code:
plt.ylabel(r'$\mathcal{r}$', fontsize=50)
and that should do it.

Related

Matplotlib version of latex command "\ell" looking extra-slanted

I use latex in matplotlib by setting
plt.rcParams.update({'mathtext.fontset': 'stix'})
plt.rcParams.update({'font.family': 'STIXGeneral'})
I am using the letter $\ell$ very often in my research and there is a small detail bothering me. As you can see below, matplotlib renders the symbol with the little loop smaller and the letter more slanted. To me it almost looks like a vertically stretched $e$. I tried using the "\mathrm{\ell}" command instead but it did not change anything.
Is there any way I could get the symbol to look normal?
PS: it looks like stackoverflow is not detecting the math mode $ for some reason. If you know how to fix it (or if I am doing something wrong) please point it out or edit the question. Thanks!
The reason is the font you are using in matplotlib. With the following settings, for example, you get the same letter as in overleaf:
import matplotlib.pyplot as plt
import numpy as np
# Example data
t = np.arange(0.0, 10, 1)
s = np.arange(0.0, 10, 1)
plt.rc('text', usetex=True)
plt.rc('font', family='serif')
plt.xlabel(r'$\ell$', fontsize=30)
plt.ylabel(r'$\ell$', fontsize=30)
plt.plot(t, s)
plt.show()
You get:
However, In Jupyterlab I could not reproduce. It used the overleaf fonts even with your settings.
This proved to be the simplest solution for me. Thanks the others for pointing out the font being the issue.
Rather than
plt.rcParams.update({'mathtext.fontset': 'stix'})
plt.rcParams.update({'font.family': 'STIXGeneral'})
I now write the first line as
plt.rcParams.update({'mathtext.fontset': 'cm'})
which works like charm. This is helpful if you are someone like me not using TeX but just the mathtext matplotlib built-in function.

Python: Matplotlib: how to print ONE text with different sizes in it?

is it possible in matplotlib to have a textbox with different font sizes within one string?
Thanks for help
I don't think this can be done without using the LaTeX text renderer. To use this do,
from matplotlib import rcParams
rcParams['text.usetex'] = True
Then you can print multi-fontsize strings using standard LaTeX syntax, e.g.
from matplotlib import pyplot as plt
ax = plt.axes()
ax.text(0.5, 0.5, r'{\tiny tiny text} normal text {\Huge HUGE TEXT}')
Sometimes the LaTeX font renderer isn't ideal (e.g. note that tick-label fonts are different than normal MPL tick labels), but it is certainly more flexible.

How to create 'normal' looking axis labels using latex in matplotlib

I have the following piece of code to create axis labels with German umlauts:
plt.xlabel('Daten')
plt.ylabel(r'$H\ddot{a}ufigkeit$')
which basically works, and prints the a-umlaut correctly, But the font of the x and y labels are now different, as the x label is printed in math mode. Changing the second line to
plt.ylabel(r'$\textrm{H\ddot{a}ufigkeit}$')
should work as far as I know (in order to create a rm like font instead of the math mode font), but gives a python error:
matplotlib.pyparsing.ParseFatalException: Expected end of math '$'
How can I fix this issue in order to have the same font on both axis, but with umlauts possible?
The non-math umlaut is \":
plt.ylabel(r'H\"{a}ufigkeit')
If you need \ddot only put the $ around that:
plt.ylabel(r'H$\ddot{a}$ufigkeit')
As an aside, the \textrm command only works in text mode. The math-mode equivalent is \mathrm:
plt.ylabel(r'$\mathrm{H\ddot{a}ufigkeit}$')
UPDATE
All of the above assume that you have told matplotlib to render with tex. To do this, add the following at the top of your code:
import matplotlib.pyplot as plt
plt.rc('text', usetex=True)

python latex font xcode

I'm trying to use Matplotlib & Python in Xcode to generate scientific graphics. My boss would like them to be in LaTeX with matching fonts. I know you can modify the fonts in python with something like this:
from matplotlib import rc
rc('font',**{'family':'serif','serif':['Computer Modern Roman']})
rc('text', usetex=True)
Unfortunately, opening or saving the figure with plt.show() or plt.savefig() gives a string of errors, eventually leading to OSError: [Errno 2] No such file or directory.
I know "Google is your friend", but I haven't managed to find anything on how to go about solving this. Any help would be greatly appreciated.
I usually find it easiest to directly specify the font file I'm after. Here's an example:
import matplotlib.pyplot as plt
import matplotlib.font_manager
from numpy import *
# cmunso.otf is a randomly selected font in my tex installation
path = '/usr/local/texlive/2012/texmf-dist/fonts/opentype/public/cm-unicode/cmunso.otf'
f0 = matplotlib.font_manager.FontProperties()
f0.set_file(path)
plt.figure()
plt.xlim(0,1.)
plt.ylim(0,1.)
d = arange(0, 1, .1)
plt.plot(d, d, "ob", label='example')
plt.text(.5, .1, 'text.. abcdef', fontproperties=f0, size=30)
plt.xlabel("x label", fontproperties=f0)
plt.legend(prop=f0, loc=2)
I'm not a font expert, but I think the reason this is easier is that font selection often has a cascading set of defaults for when the way you specify the font doesn't exactly match the way the system does. The file, though, is easy to find and specify exactly (though it's obviously less portable).
Note that for xlabel and text the keyword is fontproperties and for legend it's prop.

Matplotlib PDF export uses wrong font

I want to generate high-quality diagrams for a presentation. I’m using Python’s matplotlib to generate the graphics. Unfortunately, the PDF export seems to ignore my font settings.
I tried setting the font both by passing a FontProperties object to the text drawing functions and by setting the option globally. For the record, here is a MWE to reproduce the problem:
import scipy
import matplotlib
matplotlib.use('cairo')
import matplotlib.pylab as pylab
import matplotlib.font_manager as fm
data = scipy.arange(5)
for font in ['Helvetica', 'Gill Sans']:
fig = pylab.figure()
ax = fig.add_subplot(111)
ax.bar(data, data)
ax.set_xticks(data)
ax.set_xticklabels(data, fontproperties = fm.FontProperties(family = font))
pylab.savefig('foo-%s.pdf' % font)
In both cases, the produced output is identical and uses Helvetica (and yes, I do have both fonts installed).
Just to be sure, the following doesn’t help either:
matplotlib.rc('font', family = 'Gill Sans')
Finally, if I replace the backend, instead using the native viewer:
matplotlib.use('MacOSX')
I do get the correct font displayed – but only in the viewer GUI. The PDF output is once again wrong.
To be sure – I can set other fonts – but only other classes of font families: I can set serif fonts or fantasy or monospace. But all sans-serif fonts seem to default to Helvetica.
Basically, #Jouni’s is the right answer but since I still had some trouble getting it to work, here’s my final solution:
#!/usr/bin/env python2.6
import scipy
import matplotlib
matplotlib.use('cairo')
import matplotlib.pylab as pylab
import matplotlib.font_manager as fm
font = fm.FontProperties(
family = 'Gill Sans', fname = '/Library/Fonts/GillSans.ttc')
data = scipy.arange(5)
fig = pylab.figure()
ax = fig.add_subplot(111)
ax.bar(data, data)
ax.set_yticklabels(ax.get_yticks(), fontproperties = font)
ax.set_xticklabels(ax.get_xticks(), fontproperties = font)
pylab.savefig('foo.pdf')
Notice that the font has to be set explicitly using the fontproperties key. Apparently, there’s no rc setting for the fname property (at least I didn’t find it).
Giving a family key in the instantiation of font isn’t strictly necessary here, it will be ignored by the PDF backend.
This code works with the cairo backend only. Using MacOSX won’t work.
The "family" argument and the corresponding rc parameter are not meant to specify the name of the font can actually be used this way. There's an (arguably baroque) CSS-like font selection system that helps the same script work on different computers, selecting the closest font available. The usually recommended way to use e.g. Gill Sans is to add it to the front of the value of the rc parameter font.sans-serif (see sample rc file), and then set font.family to sans-serif.
This can be annoying if the font manager decides for some obscure reason that Gill Sans is not the closest match to your specification. A way to bypass the font selection logic is to use FontProperties(fname='/path/to/font.ttf') (docstring).
In your case, I suspect that the MacOSX backend uses fonts via the operating system's mechanisms and so automatically supports all kinds of fonts, but the pdf backend has its own font support code that doesn't support your version of Gill Sans.
This is an addition to the answers above if you came here for a non-cairo backend.
The pdf-backend of matplotlib does not yet support true type font collections (saved as .ttc files). See this issue.
The currently suggested workaround is to extract the font-of-interest from a .ttc file and save it as a .ttf file. And then use that font in the way described by Konrad Rudolph.
You can use the python-package fonttools to achieve this:
font = TTFont("/System/Library/Fonts/Helvetica.ttc", fontNumber=0)
font.save("Helvetica-regular.ttf")
As far as I can see, it is not possible to make this setting "global" by passing the path to this new .ttf file to the rc. If you are really desperate, you could try to extract all fonts from a .ttc into separate .ttf files, uninstall the .ttc and install the ttfs separately. To have the extracted font side-by-side with the original font from the .ttc, you need to change the font name with tools like FontForge. I haven't tested this, though.
Check if you are rendering the text with LaTeX, i.e., if text.usetex is set to True. Because LaTeX rendering only supports a few fonts, it largely ignores/overwrites your other fonts settings. This might be the cause.

Categories

Resources