Have you ever created a plot using Matplotlib and found its font sizes too small or too large? If yes, then you’re not alone.
Matplotlib, a data visualization library in Python, is used to create plots, graphs, and charts. By default, its font sizes may not suit everyone’s needs or preferences.
The good news is that you can easily adjust the font size of various plot elements such as titles, labels, and tick labels using Matplotlib. In this article, we’ll discuss how to change font sizes in Matplotlib plots and show some examples that illustrate its practical applications.
Changing Font Sizes in Matplotlib Plots
Changing Font Size of All Elements
When you create a plot using Matplotlib, it has several elements, such as the title, axis labels, tick labels, and legends. You may want to change the size of all the elements at once to make them more readable or consistent.
Here’s how you can do it:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Set font size of all elements
plt.rcParams.update({‘font.size’: 16})
# Add title, x label, and y label
plt.title(“Scatter Plot”)
plt.xlabel(“X-axis”)
plt.ylabel(“Y-axis”)
plt.show()
“`
In the above example, we first created a scatter plot using the `scatter()` function. Then, we updated the `rcParams` dictionary using the `update()` method to set the font size to 16.
Finally, we added a title, x label, and y label using the `title()`, `xlabel()`, and `ylabel()` functions, respectively. By setting the font size of all elements to 16, we made them more prominent and easier to read.
Changing Font Size of Specific Elements
Sometimes, you may want to change the size of a specific plot element, such as the title, axis labels, or tick labels. Here’s how you can do it:
– Changing Font Size of the Title:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Change font size of the title
plt.title(“Scatter Plot”, fontsize=20)
plt.show()
“`
In the above example, we added the `fontsize` parameter to the `title()` function and set its value to 20.
This changed the font size of the scatter plot title to 20. – Changing Font Size of the Axes Labels:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Change font size of the x and y axis labels
plt.xlabel(“X-axis”, fontsize=18)
plt.ylabel(“Y-axis”, fontsize=18)
plt.show()
“`
In the above example, we added the `fontsize` parameter to the `xlabel()` and `ylabel()` functions and set their values to 18.
This changed the font size of the scatter plot’s x and y axis labels to 18. – Changing Font Size of the Tick Labels:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Change font size of the x and y tick labels
plt.xticks(fontsize=14)
plt.yticks(fontsize=14)
plt.show()
“`
In the above example, we added the `fontsize` parameter to the `xticks()` and `yticks()` functions and set their values to 14.
This changed the font size of the scatter plot’s x and y tick labels to 14.
Examples
Now that we know how to change font sizes in Matplotlib plots let’s look at some practical examples that illustrate its applications. Example 1: Change the Font Size of All Elements
Suppose you have a scatter plot with the following data:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Add title, x label, and y label
plt.title(“Scatter Plot”)
plt.xlabel(“X-axis”)
plt.ylabel(“Y-axis”)
plt.show()
“`
The resulting plot looks like:
As you can see, the font size of the title, x label, and y label is small.
To make them bigger, let’s set the font size of all elements to 18 using the `rcParams` dictionary:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Set font size of all elements
plt.rcParams.update({‘font.size’: 18})
# Add title, x label, and y label
plt.title(“Scatter Plot”)
plt.xlabel(“X-axis”)
plt.ylabel(“Y-axis”)
plt.show()
“`
The resulting plot looks like:
As expected, the font size of the title, x label, and y label is now larger. Example 2: Change the Font Size of the Title
Suppose you have a scatter plot with the following data:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Add title
plt.title(“Scatter Plot”)
plt.show()
“`
The resulting plot looks like:
The font size of the title is small.
To make it bigger, let’s use the `fontsize` parameter in the `title()` function and set its value to 20:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Change font size of the title
plt.title(“Scatter Plot”, fontsize=20)
plt.show()
“`
The resulting plot looks like:
As expected, the font size of the title is now larger. Example 3: Change the Font Size of the Axes Labels
Suppose you have a scatter plot with the following data:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Add x label and y label
plt.xlabel(“X-axis”)
plt.ylabel(“Y-axis”)
plt.show()
“`
The resulting plot looks like:
The font size of the x and y axis labels is small.
To make them bigger, let’s use the `fontsize` parameter in the `xlabel()` and `ylabel()` functions and set their values to 18:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Change font size of the x and y axis labels
plt.xlabel(“X-axis”, fontsize=18)
plt.ylabel(“Y-axis”, fontsize=18)
plt.show()
“`
The resulting plot looks like:
As expected, the font size of the x and y axis labels is now larger. Example 4: Change the Font Size of the Tick Labels
Suppose you have a scatter plot with the following data:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
plt.show()
“`
The resulting plot looks like:
The font size of the x and y tick labels is small.
To make them bigger, let’s use the `xticks()` and `yticks()` functions and set their `fontsize` parameter to 14:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Change font size of the x and y tick labels
plt.xticks(fontsize=14)
plt.yticks(fontsize=14)
plt.show()
“`
The resulting plot looks like:
As expected, the font size of the x and y tick labels is now larger.
Restoring Default Font Sizes
If you want to restore the default font sizes after changing them, you can use the `rcParams` dictionary to reset them. For example:
“`python
import matplotlib.pyplot as plt
# Create a scatter plot
x = [1, 2, 3, 4, 5]
y = [2, 4, 6, 8, 10]
plt.scatter(x, y)
# Set font size of all elements
plt.rcParams.update({‘font.size’: 16})
# Add title, x label, and y label
plt.title(“Scatter Plot”)
plt.xlabel(“X-axis”)
plt.ylabel(“Y-axis”)
plt.show()
# Restore default font sizes
plt.rcParams.update(plt.rcParamsDefault)
“`
In the above example, we first changed the font size of all elements to 16 using the `rcParams` dictionary.
Then, we added a title, x label, and y label to the scatter plot. Finally, we reset the default font sizes using the `plt.rcParamsDefault` dictionary.
Conclusion:
In this article, we discussed how to change font sizes in Matplotlib plots. We learned how to change the font size of all elements at once and the font size of specific elements such as titles, labels, and tick labels.
We also saw some practical examples that illustrate how adjusting font sizes can improve the readability and aesthetics of plots. By using the `rcParams` dictionary, we can easily reset the default font sizes if necessary.
Hopefully, this article has helped you in customizing your plots using Matplotlib. In summary, this article has shown how to change font sizes in Matplotlib plots, including changing the font size of all elements at once and specific elements such as titles, labels, and tick labels.
Practical examples have demonstrated how adjusting font sizes can improve the readability and aesthetics of plots. Using the `rcParams` dictionary allows you to reset the default font sizes if required.
Adjusting font sizes is an essential aspect of plot customization, and it can make a significant difference in your data visualizations. By applying the learnings from this article, you can create more polished and effective Matplotlib plots.