Matplotlib – How to insert a degree symbol into a Python plot?

To insert a degree symbol into a Python plot, you can use LaTeX representation with the syntax $^\circ$. This is particularly useful when plotting temperature data or angular measurements.

Steps

• Create data points for pV, nR and T using numpy
• Plot pV and T using plot() method
• Set xlabel for pV using xlabel() method
• Set the label for temperature with degree symbol using ylabel() method
• To display the figure, use show() method

Example

Let's create a simple temperature vs pressure×volume plot with a degree symbol in the y-axis label ?

import numpy as np
from matplotlib import pyplot as plt

plt.rcParams["figure.figsize"] = [7.00, 3.50]
plt.rcParams["figure.autolayout"] = True

pV = np.array([3, 5, 1, 7, 10, 9, 4, 2])
nR = np.array([31, 15, 11, 51, 12, 71, 41, 13])
T = np.divide(pV, nR)

plt.plot(pV, T, c="red")
plt.xlabel("Pressure x Volume")
plt.ylabel("Temperature ($^\circ$C)")
plt.show()

Output

The above code will display a line plot with the y-axis labeled as "Temperature (°C)" where the degree symbol is properly rendered.

Alternative Methods

You can also use Unicode character or raw string formatting ?

import matplotlib.pyplot as plt
import numpy as np

# Method 1: Unicode character
plt.ylabel("Temperature (\u00B0C)")

# Method 2: Raw string with LaTeX
plt.ylabel(r"Temperature ($^\circ$C)")

# Method 3: For angles in degrees
plt.xlabel("Angle ($^\circ$)")

plt.show()

Key Points

• $^\circ$ − LaTeX representation (most common)
• \u00B0 − Unicode character for degree symbol
• r"..." − Raw string prevents escape character issues
• Works in titles, axis labels, and text annotations

Conclusion

The LaTeX representation $^\circ$ is the most reliable method to insert degree symbols in Matplotlib plots. Use raw strings with r"" or Unicode \u00B0 as alternatives when needed.