Data Visualisation using PyPlot [ Class 12 ]
Matplotlib is the whole python package/ library used to create 2D graphs and plots by using python scripts. PyPlot is a module in matplotlib, which supports a very wide variety of graphs and plots namely – histogram, bar charts, power spectra, error charts etc.
It is used along with NumPy to provide an environment for MatLab.
Pyplot provides the state-machine interface to the plotting library in matplotlib.It means that figures and axes are implicitly and automatically created to achieve the desired plot. For example, a calling plot from pyplot will automatically create the necessary figure and axes to achieve the desired plot.
Setting a title will then automatically set that title to the current axes object. The pyplot interface is generally preferred for non-interactive plotting (i.e.,scripting).
The line chart is represented by a series of data points connected with a straight line.Generally, line charts are
used to display trends over time. A line chart or line graph can be created using the plot() function available in pyplot library.We can not only just plot a line but we can explicitly define the grid, the x and y-axis scale and labels, title and display options.
Sample Python Program to Draw Line Chart
# program to print scatter graph on the screen # made by : rakesh kumar import matplotlib.pyplot as plt import numpy as np x = ['Delhi', 'Banglore', 'Chennai', 'Pune'] y = [250, 300, 260, 400] plt.xlabel('City') plt.ylabel('Sales in Million') plt.title('Sales Recorded in Major Cities') plt.plot(x, y) plt.show()
The output of above line chart python program is as follows
Bar Chart using Python PyPlot
A bar chart/bar graph, is a very common two-dimensional data visualization made up of rectangular bars, each for a specific category and it’s length represents the value of that category.
Python Program to draw Bar chart
# program to print bar graph on the screen # made by : rakesh kumar import matplotlib.pyplot as plt x = ['Delhi', 'Banglore', 'Chennai', 'Pune'] y = [250, 300, 260, 400] plt.xlabel('City') plt.ylabel('Sales in Million') plt.title('Sales Recorded in Major Cities') plt.bar(x, y) plt.show()
The output of the above Bargraph program is
Pie Chart using PyPlot
A pie graph/pie chart is a specialized graph used in statistics. The independent variable is plotted around a
circle.Pie Charts shows proportions and percentages between categories, by dividing a circle into proportional
segments/parts. Each arc length represents a proportion of each category, while the full circle represents the total sum of all the data, equal to 100%.
Python Program to draw Pie-chart
# program to print pie graph on the screen # made by : rakesh kumar import matplotlib.pyplot as plt import numpy as np x = ['Delhi','Banglore','Chennai','Pune','Ghaziabad','Udupi'] y = [250,300,260,400,599,320] plt.pie(y,labels=x,autopct='%1.2f',startangle=90,explode=(0,0.1,0,0,0.2,0)) plt.show()
The output of the Python Pie-chart Program
Well, these are some very simple data visualization using pyplot. I think now you have the idea. If you have any queries regarding data visualization using python Pyplot. Please send us your request via email.