Chapter 7.10, Problem 28CP

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The functions “xlabel()” and “ylabel()” are used to create labels to the axes in the graph.

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Explanation of Solution

Function “xlabel()”:

• • The “xlabel()” function creates a label to the X axis.
• • This function gives a meaningful name to the X axis, so that, the information represented by the X axis will be understood clearly.
• • This function “xlabel()” takes a string as its input parameters.

Syntax:

The “xlabel()” function has the below format.

#Add label to X axis

plt.xlabel(label1)

Explanation:

Here,

• • “xlabel()” is the function that produces a label to the X axis.
• • The variable “label1” is a string that is going to name the X axis.

Example program:

The below example shows how to use the “xlabel()” function in Python,

#Import the files

import matplotlib.pyplot as plt

#Create a list to have the X coordinates of data points

xcoord = [1, 2, 3, 4]

#Create a list to have the Y coordinates of data points

ycoord = [2, 4, 6, 8]

#Call the function

plt.plot(xcoord, ycoord)

#Add label to the X axis

plt.xlabel('X axis')

#Show the graph

plt.show()

Sample Output:

Screenshot of the graph

In the above code,

• • The list “xcoord” represents the X coordinates of all the data points.
• • The list “ycoord” represents the Y coordinates of all the data points.
• • Then, the lists “xcoord” and “ycoord” are passed as input parameters to the “plot()” function to create a line graph.
• • The function “xlabel()” is called to assign the label “X axis” to the X axis.
• • Then, the graph is shown using “show()” function.

Function “ylabel()”:

• • The label to the Y axis is created by the function “ylabel()” ...