A pie chart is a pictorial graph in the shape of a circle, with different wedges or segments representing different data values.
We draw pie charts in matplotlib
using the method pie()
, which is found in the pyplot
module.
pyplot.pie()
The pie()
method takes the data array which represents the wedge sizes of the pie chart.
Now let’s explore a basic example of pie chart.
from matplotlib.pyplot import pie, showfrom numpy import arraydata_set = array([25, 20, 50, 15])pie(data_set)show()
Line 1: We import pie()
and show()
from the matplotlib.pyplot
module.
Line 2: We import array()
from NumPy
library.
Line 4: We use the array()
method to create a data array.
Line 6: We use the pie()
method to plot a pie chart.
Line 7: We use the show()
method to show our plot.
After exploring the basic example, let's enhance our understanding with an example of a pie chart with some customization.
from matplotlib.pyplot import pie, showfrom numpy import arraydata_set = array([25, 20, 50, 15])labels = ['A', 'B', 'C', 'D']colors = ['gold', 'yellowgreen', 'lightcoral', 'lightskyblue']explode = (0, 0.1, 0, 0) # "explode" the second slice (B)pie(data_set, explode=explode, labels=labels, colors=colors, autopct='%1.1f%%', shadow=True)show()
Line 1: This line imports the pie()
and show()
functions from the matplotlib.pyplot
module. pie()
is used to create pie charts, while show()
is used to display the plot.
Line 2: Here, we import the array()
function from the NumPy library. This function is used to create an array, a fundamental data structure in numerical computing.
Line 4: We define a dataset using the array()
function. In this case, we create an array with values [25, 20, 50, 15]
, which represent the sizes of different slices in the pie chart.
Line 5: We defined am labels
variable, which a list of strings (['A', 'B', 'C', 'D']
) representing the labels assigned to each slice of the pie chart. These labels will be displayed next to their respective slices.
Line 6: We defined a variable called colors, which is a list of color names or RGB tuples (['gold', 'yellowgreen', 'lightcoral', 'lightskyblue']
) specifying the colors of the pie chart slices. Each color corresponds to a specific slice, providing visual differentiation.
Line 9: This line calls the pie()
function to create a pie chart. We pass the data_set
array as an argument to the function, which specifies the sizes of the slices in the pie chart.
Line 10: Finally, we call the show()
function to display the plot on the screen. This function is necessary to actually render the plot and show it to the user.