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pythonmatplotlibplotfontsannotate

Matplotlib annotate change font

I am trying to change the font type (from deja-vu to lets' say comic sans or calibri) for the text that appears along with matplotlib's annotate function. However, though I can change the font for all the other elements in the plot, it won't change it for the annotated text. Any help? Below is what I'm working with and how I globally set the font. You'll notice the difference in fonts when comparing the style of "1" on the plots. enter image description here

import numpy as np
import os, glob
import pandas as pd
import matplotlib.pyplot as plt
import matplotlib.font_manager
from matplotlib import rcParams

import pdb
matplotlib.font_manager._rebuild()
# THIS SETS ALL THE RELEVANT FONT STYLE FOR PLOTS
rcParams['font.family'] = 'sans-serif'
rcParams['font.weight'] = 'regular'  #can omit this, it's the default
rcParams['font.sans-serif'] = ['calibri']

# test code
ax = plt.figure().add_subplot()
x,y = np.arange(10),np.arange(10)
ax.plot(x,y)
ax.annotate(r'$100^\circ$',
            xy=(1.1, 0.1), xycoords='axes fraction',
            xytext=(1.1, 0.8), textcoords='axes fraction',
            arrowprops=dict(facecolor='black', shrink=0.01),
            horizontalalignment='center', verticalalignment='top',
            fontsize=15)
Solution

  • The problem is, it's a mathematical text... if you change regular text's font characteristics, you're not going to affect the fonts that Matplotlib uses for mathematical text.

    Of course you can modify the font used in mathematical text (is there anything in Matplotlib that you cannot modify?)

    Writing mathematical expressions

    [...] Mathtext can use DejaVu Sans (default), DejaVu Serif, the Computer Modern fonts (from (La)TeX), STIX fonts (with are designed to blend well with Times), or a Unicode font that you provide. The mathtext font can be selected with the customization variable mathtext.fontset (see Customizing Matplotlib with style sheets and rcParams).