Introduction to Python for MATLAB Users/

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2D Charts

2D Charts

Learn to create various 2D charts in Python with the knowledge of MATLAB.

We'll cover the following...

2D charts are graphical representations of data that use a 2D plane to display information. We are going to create some common 2D charts in MATLAB and Python.

The bar chart

As the name implies, a bar chart is a graph that uses bars to represent different categories of data. The length of each bar represents the value of that category. Bars can be vertical or horizontal.

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The bar chart
The bar chart

For the vertical bar charts, we use the bar() function in MATLAB. Let’s see the implementation of the bar() function.

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index = 1:5;
values = [6,2,7,3,8];
f = figure();
bar(index,values,'FaceColor',[.42 .37 .73])
xticklabels({'A','B','C','D','E'})
legend('First')
title('A Bar Chart',"fontsize", 16,'Color','r');
ylim([0 10])
xlabel('Category')
ylabel('Bar Value')

  • Line 1: We initialize the index array with x-axis values.

  • Line 2: We initialize the values array with y-axis values.

  • Line 4: Using the bar() function, we plot a bar chart using four arguments:

    • The first argument is the x-axis values.

    • The second argument is the y-axis values.

    • The third argument specifies which property we are going to set. In this case, it is FaceColor.

    • The fourth argument is the value of color. In this case, we use the RGB percentage value of [.42 .37 .73].

  • Line 5: We use the xticklabel() command to specify labels on the x-axis with respect to each index (x-axis) value. It will be enclosed in curly brackets {} and separated by a comma ,.

  • Line 6: We create a legend using the legend() function to categorize different types of data.

  • Line 7: We set a figure title using the title() function. It has five arguments:

    • The first argument is the title of the figure. It will be written as a string.

    • The second and fourth arguments define a property. Here, we have fontsize and color to set the font size and color of the title.

    • The third and fifth arguments represent the value of the property. Here, we have fontsize equal to 16 and color equal to r means red.

  • Line 8: We use ylim command to set the upper and lower limits of the y-axis. The first argument is the lower limit, followed by an upper limit.

In Python, we use plt.bar() function from the Matplolib library to plot a bar chart.

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import matplotlib.pyplot as plt
import numpy as np
index = np.arange(1,6)
values = np.array([6,2,7,3,8])
plt.figure(dpi=300)
plt.bar(index,values,color = (.42, .37, .73))
plt.xticks(index,['A','B','C','D','E'])
plt.legend(['First'])
plt.title('A Bar Chart',fontsize=16,color = 'red')
plt.ylim(0,10)
plt.xlabel('Category')
plt.ylabel('Bar Value')
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