Line graphs are helpful for visualizing how a variable changes over time.

Some possible data that would be displayed with a line graph:

• average prices of gasoline over the past decade
• weight of an individual over the past couple of months
• average temperature along a line of longitude over different latitudes

Using Matplotlib methods, the following code will create a simple line graph using .plot() and display it using .show() :

x_values = [0, 1, 2, 3, 4]
y_values = [0, 1, 4, 9, 16]
plt.plot(x_values, y_values)
plt.show()

• x_values is a variable holding a list of x-values for each point on our line graph
• y_values is a variable holding a list of y-values for each point on our line graph
• plt is the name we have given to the Matplotlib module we have imported at the top of the code
• plt.plot(x_values, y_values) will create the line graph
• plt.show() will actually display the graph

Our graph would look like this:

Let’s get some practice with plotting lines.