LaTeX integration for papers in Matplotlib - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Matplotlib plot with LaTeX formatted title

What is the output of this code snippet that uses LaTeX in the plot title?

Matplotlib

import matplotlib.pyplot as plt
plt.plot([1, 2, 3], [1, 4, 9])
plt.title(r'$y = x^2$')
plt.savefig('plot.png')
plt.close()
print('Plot saved with LaTeX title')

A The plot is saved but the title shows the raw string '$y = x^2$' without formatting

B The plot is saved with the title showing y = x squared formatted using LaTeX math style

C The code raises a SyntaxError due to incorrect LaTeX syntax in the title

D The plot is saved but the title is empty because LaTeX is not supported

💡 Hint

Look at how raw strings and LaTeX math mode are used in matplotlib titles.

Matplotlib supports LaTeX math formatting in titles when the string is prefixed with r and enclosed in dollar signs. This renders the title as a math expression.

❓ data_output

intermediate

Effect of rcParams on LaTeX font in matplotlib

Given this code, what font family will be used in the plot labels?

Matplotlib

import matplotlib.pyplot as plt
plt.rcParams.update({
    'text.usetex': True,
    'font.family': 'serif',
    'font.serif': ['Palatino'],
})
plt.plot([0, 1], [0, 1])
plt.xlabel(r'$x$ axis')
plt.ylabel(r'$y$ axis')
plt.savefig('latex_font_plot.png')
plt.close()
print(plt.rcParams['font.family'])

A ['sans-serif']

B ['monospace']

C ['Palatino']

D ['serif']

💡 Hint

Check the value of plt.rcParams['font.family'] after update.

The 'font.family' key is set to 'serif', which is a generic family. The specific serif font 'Palatino' is set in 'font.serif' but plt.rcParams['font.family'] returns the generic family list.

❓ visualization

advanced

Rendering complex LaTeX in matplotlib legend

Which option produces a plot with a legend showing the formula $\alpha = \frac{1}{\sqrt{2\pi\sigma^2}} e^{-\frac{(x-\mu)^2}{2\sigma^2}}$ correctly rendered?

Matplotlib

import matplotlib.pyplot as plt
import numpy as np
x = np.linspace(-3, 3, 100)
y = np.exp(-x**2 / 2) / np.sqrt(2 * np.pi)
plt.plot(x, y, label='')
plt.legend()
plt.show()

A plt.plot(x, y, label=r'$\alpha = \frac{1}{\sqrt{2\pi\sigma^2}} e^{-\frac{(x-\mu)^2}{2\sigma^2}}$')

B plt.plot(x, y, label='$\alpha = \frac{1}{\sqrt{2\pi\sigma^2}} e^{-\frac{(x-\mu)^2}{2\sigma^2}}$')

C plt.plot(x, y, label='\alpha = \frac{1}{\sqrt{2\pi\sigma^2}} e^{-\frac{(x-\mu)^2}{2\sigma^2}}')

D plt.plot(x, y, label=r'\alpha = \frac{1}{\sqrt{2\pi\sigma^2}} e^{-\frac{(x-\mu)^2}{2\sigma^2}}')

💡 Hint

Raw strings (r'') help avoid escape sequence errors in LaTeX strings.

Using a raw string with r'' and enclosing the LaTeX math expression in dollar signs ensures correct rendering in matplotlib legends.

🔧 Debug

advanced

Identify the error in LaTeX integration with matplotlib

What error does this code raise when run?

Matplotlib

import matplotlib.pyplot as plt
plt.rcParams['text.usetex'] = True
plt.title('$E = mc^2$')
plt.plot([1, 2, 3], [1, 4, 9])
plt.show()

A TypeError: unsupported operand type(s) for ^: 'str' and 'int'

B SyntaxError: invalid syntax in LaTeX string

C RuntimeError: LaTeX was not found on the system

D No error, plot displays correctly

💡 Hint

Check if LaTeX is installed and accessible by matplotlib.

If LaTeX is not installed or not in the system path, matplotlib raises a RuntimeError when usetex=True is set.

🚀 Application

expert

Creating a publication-quality plot with LaTeX labels and custom preamble

Which code snippet correctly sets a custom LaTeX preamble to use the 'amsmath' package and renders the plot with LaTeX labels?

A

import matplotlib.pyplot as plt
plt.rcParams['text.usetex'] = True
plt.rcParams['text.latex.preamble'] = r'\usepackage{amsmath}'
plt.plot([0, 1], [0, 1])
plt.xlabel(r'\alpha + \beta')
plt.show()

B

import matplotlib.pyplot as plt
plt.rcParams.update({
    'text.usetex': True,
    'text.latex.preamble': '\usepackage{amsmath}',
})
plt.plot([0, 1], [0, 1])
plt.xlabel('$\alpha + \beta$')
plt.show()

C

import matplotlib.pyplot as plt
plt.rcParams['text.usetex'] = True
plt.rcParams['text.latex.preamble'] = '\usepackage{amsmath}'
plt.plot([0, 1], [0, 1])
plt.xlabel('$\alpha + \beta$')
plt.show()

D

import matplotlib.pyplot as plt
plt.rcParams.update({
    'text.usetex': True,
    'text.latex.preamble': r'\usepackage{amsmath}',
})
plt.plot([0, 1], [0, 1])
plt.xlabel(r'$\alpha + \beta$')
plt.show()

💡 Hint

Use raw strings for LaTeX preamble and labels to avoid escape issues.

Option A correctly uses raw strings for the LaTeX preamble and label, ensuring proper escaping and rendering with usetex=True.