How to add labels and titles to a plot in matplotlib

Overview

Plots in MatplotlibA comprehensive library for creating static, animated, and interactive visualizations in Python. represent the visualization of the given data. These plots require labels (on x and y-axis) and titles. Every plot has an x and y-axis. These axes represent the values of the plotted data.

How to add labels to a plot

In matplotlib, we use the pyplot.xlabel() and pyplot.ylabel() functions to label the x and y-axis of the plot, respectively.

Example

Let’s create a plot and label its x and y-axes as follows:

import matplotlib.pyplot as plt
import numpy as np
x = np.array([1, 5])
y = np.array([10, 20])
plt.plot(x, y)
# using the xlabel and ylabel functions
plt.xlabel("x axis")
plt.ylabel("y axis")
plt.show()
Output of the code

Explanation

  • Line 1: We import the pyplot module from the matplot library.
  • Line 2: We import the numpy module.
  • Line 4: We use the numpy.array() method to create an array variable x.
  • Line 5: We use the numpy.array() method to create another array variable, y.
  • Line 7: We use the pyplot.plot() method to plot y against x (that is, x on the x-axis and y on the y-axis).
  • Line 10: We use the pyplot.xlabel() method to label the x-axis of our plot.
  • Line 11: We use the pyplot.ylabel() method to label the y-axis of our plot.
  • Line 12: We use the pyplot.show() method to ask Python to show us our plot.

How to add a title to a plot

In Matplotlib, we use the pyplot.title() method to give a title to a plot.

Example

Let’s create a plot and give it a title, as follows:

import matplotlib.pyplot as plt
import numpy as np
x= np.array([1, 5])
y = np.array([10, 20])
plt.plot(x, y)
# usig the title() method
plt.title('Y against X')
# using the xlabel() and ylabel() methods
plt.xlabel("x axis")
plt.ylabel("y axis")
plt.show()
Output of the code

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