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Matplotlib font common font with LaTeX

I can't seem to set the same font for both regular text and mathematical numbers
I am trying to set a font using Matplotlib for a draft article, and the font I need to use is Libertine. Ideally I would just let LaTeX do all the formatting, but it seems set on formatting the maths font with computer modern:
import matplotlib as mpl
rc_fonts = {
"font.family": "serif",
"font.size": 20,
'figure.figsize': (5, 3),
"text.usetex": True,
'text.latex.preview': True,
'text.latex.preamble': [
r"""
\usepackage[libertine]{newtxmath}
\usepackage{libertine}
"""],
}
mpl.rcParams.update(rc_fonts)
import matplotlib.pylab as plt
with the trivial plot
plt.ion()
plt.clf()
plt.plot(range(10))
plt.title("something 0,2,4,6,8 $e=mc^2$")
produces (compare the "2"s)
If instead I use
rc_fonts = {
"font.family": "serif",
'font.serif': 'Linux Libertine O',
"font.size": 20,
'figure.figsize': (5, 3),
}
then the numbers now match but the maths is not using LaTeX (unsurprisingly):
To get the libertine fonts I downloaded them from https://ctan.org/tex-archive/install/fonts and installed them using the description from https://dallascard.github.io/changing-the-font-in-matplotlib.html (http://andresabino.com/2015/08/18/fonts-and-matplotlib/ seems related). The following questions seem to touch upon the issue, but I can't get a solution to work from them yet:
Matplotlib, Consistent font using latex
how to set up a custom font with custom path to matplotlib global font?
Unable to use custom fonts in matplotlib

Based on the comment pointed out by #gboffi, it seems this is not an issue with Matplotlib at all, but can be replicated by LaTeX using the preamble. Switching the order of the packages, which is the order as seen in answers to this question: https://tex.stackexchange.com/questions/544474/libertine-and-math-numbers then the issue is resolved:
rc_fonts = {
"font.family": "serif",
"font.size": 20,
'figure.figsize': (5, 3),
"text.usetex": True,
'text.latex.preview': True,
'text.latex.preamble': [
r"""
\usepackage{libertine}
\usepackage[libertine]{newtxmath}
"""],
}
gives

How to change font in $$ which is in math form in python

When I tried to polt a figure with matplotlib, I wrote the x axis label with both text and "math text". Because I have to write a chemical formula in the label, it was written as '$CO_2$ concentration'. The question is that I hope the font should be times new roman, but I cannot change the font in the dollar sign somehow. Is there anyone who can help me fix it? Thank you very much!
import numpy as np
import matplotlib.pyplot as plt
import pandas as pd
xf1 = pd.read_excel('1812_GPT.xlsx',sheetname= 'PVD_CO2CH4_600',usecols=[1])
deltapx1 = pd.read_excel('1812_GPT.xlsx',sheetname= 'PVD_CO2CH4_600',usecols=[3])
Px1 = pd.read_excel('1812_GPT.xlsx',sheetname= 'PVD_CO2CH4_600',usecols=[5])
ax1 = plt.subplot(111)
l1, = ax1.plot(xf1,Px1,'s',markerfacecolor='black')
font1 = {'family' : 'Times New Roman',
'weight' : 'normal',
'size' : 14,
}
ax1.set_xlabel(r'$CO_2$ pressure', font1)
ax1.set_ylabel(r'$CO_2$ concentration', font1)
plt.show()
This is the picture link, you may see the pic and find that "CO2" is not in Times new roman.
https://flic.kr/p/2dmh8pj

I don't think it's easily possible to change any mathtext to an arbitrary font. However, in case of "CO_2" that consists only of regular symbols, you may use \mathdefault{} to make the mathtext use the symbols from the regular font.
import matplotlib.pyplot as plt
plt.rcParams["font.family"] = "serif"
plt.rcParams["font.serif"] = ["Times New Roman"] + plt.rcParams["font.serif"]
fig, ax = plt.subplots()
ax.set_xlabel(r'$\mathdefault{CO_2}$ pressure')
ax.set_ylabel(r'$\mathdefault{CO_2}$ concentration')
plt.show()
Something like r"$\mathdefault{\sum_\alpha^\beta\frac{i}{9}}$ would still be rendered in the usual default math fontset (except the "i" and the 9, which are of course present in Times New Roman).
For the general case, you may also change the complete math fontset to any of the available, cm, stix, stixsans, dejavuserif, dejavusans. The closest to "Times New Roman" would be stix.
import matplotlib.pyplot as plt
rc = {"font.family" : "serif",
"mathtext.fontset" : "stix"}
plt.rcParams.update(rc)
plt.rcParams["font.serif"] = ["Times New Roman"] + plt.rcParams["font.serif"]
fig, ax = plt.subplots()
ax.set_xlabel(r'$CO_2$ pressure')
ax.set_ylabel(r'$CO_2$ concentration')
plt.show()
A general recommendation for reading would be the MathText tutorial.

I find it better to define the whole font family at once, rather than independently (assuming you want the same font). Give this a try
plt.rc('text', usetex=True )
plt.rc('font', family='Times New Roman', weight='normal', size=14)
plt.rcParams['mathtext.fontset'] = 'Times New Roman'
ax1.set_xlabel('$CO_2$ pressure')
ax1.set_ylabel('$CO_2$ concentration')

How to use Font Awesome symbol as marker in matplotlib

Is it possible to use a font-awesome icon as a marker in a scatterplot with matplotlib?
Or is it possible to use it as a font and put the icon as a 'text'?
This question has originally been asked here, but has been closed for an unknown reason. Since I consider it a valid and useful problem, which hasn't been addressed anywhere on Stackoverflow and sure deserves an answer, I will simply ask it again.

FontAwesome is available from here.
It provides its icons as vector graphics and as well as as otf-font.
Use FontAwesome otf font
Matplotlib cannot natively read vector graphics, but it can load otf-fonts.
After downloading the FontAwesome package you can access the font via a matplotlib.font_manager.FontProperties object, e.g.
fp = FontProperties(fname=r"C:\Windows\Fonts\Font Awesome 5 Free-Solid-900.otf")
Create texts
The FontProperties can be the input for matplotlib text objects
plt.text(.6, .4, "\uf16c", fontproperties=fp)
Unfortunately, using the FontAwesome ligatures is not possible. Hence the individual symbols need to be accessed via their UTF8 key. This is a little cumbersome, but the cheatsheet can come handy here. Storing those needed symbols in a dictionary with a meaningful name may make sense.
Example:
from matplotlib.font_manager import FontProperties
import matplotlib.pyplot as plt
fp1 = FontProperties(fname=r"C:\Windows\Fonts\Font Awesome 5 Brands-Regular-400.otf")
fp2 = FontProperties(fname=r"C:\Windows\Fonts\Font Awesome 5 Free-Solid-900.otf")
symbols = dict(cloud = "\uf6c4", campground = "\uf6bb", hiking = "\uf6ec",
mountain = "\uf6fc", tree = "\uf1bb", fish = "\uf578",
stackoverflow = "\uf16c")
fig, (ax, ax2) = plt.subplots(ncols=2, figsize=(6.2, 2.2), sharey=True)
ax.text(.5, .5, symbols["stackoverflow"], fontproperties=fp1, size=100,
color="orange", ha="center", va="center")
ax2.stackplot([0,.3,.55,.6,.65,1],[.1,.2,.2,.2,.2,.15],[.3,.2,.2,.3,.2,.2],
colors=["paleturquoise", "palegreen"])
ax2.axis([0,1,0,1])
ax2.text(.6, .4, symbols["mountain"], fontproperties=fp2, size=16, ha="center")
ax2.text(.09, .23, symbols["campground"], fontproperties=fp2, size=13)
ax2.text(.22, .27, symbols["hiking"], fontproperties=fp2, size=14)
ax2.text(.7, .24, symbols["tree"], fontproperties=fp2, size=14,color="forestgreen")
ax2.text(.8, .33, symbols["tree"], fontproperties=fp2, size=14,color="forestgreen")
ax2.text(.88, .28, symbols["tree"], fontproperties=fp2, size=14,color="forestgreen")
ax2.text(.35, .03, symbols["fish"], fontproperties=fp2, size=14,)
ax2.text(.2, .7, symbols["cloud"], fontproperties=fp2, size=28,)
plt.show()
Create markers
Creating a lot of texts like above is not really handy. To have the icons as markers would be nicer for certain applications. Matplotlib does have the ability to use utf symbols as markers, however, only through the mathtext functionality. Getting an otf font to be used as mathfont in matplotlib was unsuccessful in my trials.
An alternative is to create a matplotlib.path.Path from the symbol. This can be done via a matplotlib.textpath.TextToPath instance, which is unfortunately undocumented. The TextToPath has a method get_text_path taking a fontproperty and a string as input and returning the vertices and codes from which to create a Path. A Path can be used as a marker, e.g. for a scatter plot.
v, codes = TextToPath().get_text_path(fp, \uf6fc)
path = Path(v, codes, closed=False)
plt.scatter(..., marker=path)
Some example:
import numpy as np; np.random.seed(32)
from matplotlib.path import Path
from matplotlib.textpath import TextToPath
from matplotlib.font_manager import FontProperties
import matplotlib.pyplot as plt
fp = FontProperties(fname=r"C:\Windows\Fonts\Font Awesome 5 Free-Solid-900.otf")
symbols = dict(cloud = "\uf6c4", campground = "\uf6bb", hiking = "\uf6ec",
mountain = "\uf6fc", tree = "\uf1bb", fish = "\uf578",
stackoverflow = "\uf16c")
fig, ax = plt.subplots()
def get_marker(symbol):
v, codes = TextToPath().get_text_path(fp, symbol)
v = np.array(v)
mean = np.mean([np.max(v,axis=0), np.min(v, axis=0)], axis=0)
return Path(v-mean, codes, closed=False)
x = np.random.randn(4,10)
c = np.random.rand(10)
s = np.random.randint(120,500, size=10)
plt.scatter(*x[:2], s=s, c=c, marker=get_marker(symbols["cloud"]),
edgecolors="none", linewidth=2)
plt.scatter(*x[2:], s=s, c=c, marker=get_marker(symbols["fish"]),
edgecolors="none", linewidth=2)
plt.show()

Adding to ImportanceOfBeingErnest's great answer: you can easily get the UTF keys by using the fontawesome Python package.
Install via pip:
pip install fontawesome
Usage:
import fontawesome as fa
# icons dict converts to correct utf-8 code:
fa.icons['thumbs-up']

Matplotlib multi-colored title [duplicate]

Is there a way in matplotlib to partially specify the color of a string?
Example:
plt.ylabel("Today is cloudy.")
How can I show "today" as red, "is" as green and "cloudy." as blue?

I only know how to do this non-interactively, and even then only with the 'PS' backend.
To do this, I would use Latex to format the text. Then I would include the 'color' package, and set your colors as you wish.
Here is an example of doing this:
import matplotlib
matplotlib.use('ps')
from matplotlib import rc
rc('text',usetex=True)
rc('text.latex', preamble='\usepackage{color}')
import matplotlib.pyplot as plt
plt.figure()
plt.ylabel(r'\textcolor{red}{Today} '+
r'\textcolor{green}{is} '+
r'\textcolor{blue}{cloudy.}')
plt.savefig('test.ps')
This results in (converted from ps to png using ImageMagick, so I could post it here):

Here's the interactive version. Edit: Fixed bug producing extra spaces in Matplotlib 3.
import matplotlib.pyplot as plt
from matplotlib import transforms
def rainbow_text(x,y,ls,lc,**kw):
"""
Take a list of strings ``ls`` and colors ``lc`` and place them next to each
other, with text ls[i] being shown in color lc[i].
This example shows how to do both vertical and horizontal text, and will
pass all keyword arguments to plt.text, so you can set the font size,
family, etc.
"""
t = plt.gca().transData
fig = plt.gcf()
plt.show()
#horizontal version
for s,c in zip(ls,lc):
text = plt.text(x,y,s+" ",color=c, transform=t, **kw)
text.draw(fig.canvas.get_renderer())
ex = text.get_window_extent()
t = transforms.offset_copy(text._transform, x=ex.width, units='dots')
#vertical version
for s,c in zip(ls,lc):
text = plt.text(x,y,s+" ",color=c, transform=t,
rotation=90,va='bottom',ha='center',**kw)
text.draw(fig.canvas.get_renderer())
ex = text.get_window_extent()
t = transforms.offset_copy(text._transform, y=ex.height, units='dots')
plt.figure()
rainbow_text(0.05,0.05,"all unicorns poop rainbows ! ! !".split(),
['red', 'orange', 'brown', 'green', 'blue', 'purple', 'black'],
size=20)

Extending Yann's answer, LaTeX coloring now also works with PDF export:
import matplotlib
from matplotlib.backends.backend_pgf import FigureCanvasPgf
matplotlib.backend_bases.register_backend('pdf', FigureCanvasPgf)
import matplotlib.pyplot as plt
pgf_with_latex = {
"text.usetex": True, # use LaTeX to write all text
"pgf.rcfonts": False, # Ignore Matplotlibrc
"pgf.preamble": [
r'\usepackage{color}' # xcolor for colours
]
}
matplotlib.rcParams.update(pgf_with_latex)
plt.figure()
plt.ylabel(r'\textcolor{red}{Today} '+
r'\textcolor{green}{is} '+
r'\textcolor{blue}{cloudy.}')
plt.savefig("test.pdf")
Note that this python script sometimes fails with Undefined control sequence errors in the first attempt. Running it again is then successful.

After trying all the methods above, I return back to my stupid but easy method, using plt.text. The only problem is that you need to adjust the spaces between each word. You may need to adjust the positions several times, but I still like this way, because it
saves you from installing tex compilers,
does not require any special backends, and
free you from configuring matplotlib rc and configure back, or it may slows down your other plots, due to usetex=True
import matplotlib.pyplot as plt
fig, ax = plt.subplots()
label_x = -0.15
ax.text(label_x, 0.35, r"Today", color='red', rotation='vertical', transform=ax.transAxes)
ax.text(label_x, 0.5, r"is", color='green', rotation='vertical', transform=ax.transAxes)
ax.text(label_x, 0.55, r"cloudy", color='blue', rotation='vertical', transform=ax.transAxes)

How do I get 'matplotlib' to use my LaTeX sans font by default [duplicate]

The following script:
import matplotlib
matplotlib.use('Agg')
import matplotlib.pyplot as mpl
mpl.rc('font', family='sans-serif')
mpl.rc('text', usetex=True)
fig = mpl.figure()
ax = fig.add_subplot(1,1,1)
ax.text(0.2,0.5,r"Math font: $451^\circ$")
ax.text(0.2,0.7,r"Normal font (except for degree symbol): 451$^\circ$")
fig.savefig('test.png')
is an attempt to use a sans-serif font in matplotlib with LaTeX. The issue is that the math font is still a serif font (as indicated by the axis numbers, and as demonstrated by the labels in the center). Is there a way to set the math font to also be sans-serif?

I always have text.usetex = True in my matplotlibrc file. In addition to that, I use this as well:
mpl.rcParams['text.latex.preamble'] = [
r'\usepackage{siunitx}', # i need upright \micro symbols, but you need...
r'\sisetup{detect-all}', # ...this to force siunitx to actually use your fonts
r'\usepackage{helvet}', # set the normal font here
r'\usepackage{sansmath}', # load up the sansmath so that math -> helvet
r'\sansmath' # <- tricky! -- gotta actually tell tex to use!
]
Hope that helps.

The easiest way is to use matplotlib's internal TeX, e.g.:
import pylab as plt
params = {'text.usetex': False, 'mathtext.fontset': 'stixsans'}
plt.rcParams.update(params)
If you use an external LaTeX, you can use, e.g., CM Bright fonts:
params = {'text.usetex': True,
'text.latex.preamble': [r'\usepackage{cmbright}', r'\usepackage{amsmath}']}
plt.rcParams.update(params)
Note, that the CM Bright font is non-scalable, and you'll not be able to save PDF/PS!
Same with other options with external LaTeX I've found so far.

This will enable you to use the Computer Modern Sans font if you, as I, prefer it over Helvetica:
mpl.rcParams['text.usetex'] = True
mpl.rcParams['text.latex.preamble'] = [r'\usepackage[cm]{sfmath}']
mpl.rcParams['font.family'] = 'sans-serif'
mpl.rcParams['font.sans-serif'] = 'cm'