How To Use Matplotlib subplot2grid() With Examples

The matplotlib.pyplot module provides the function subplot2grid(), which creates axes objects ( plot areas ) at specific locations on the canvas. Not only that, but it can also use a different number of rows and columns to create drawing areas with different spans. Unlike the subplot() and subplots() functions, the subplot2gird() function splits the canvas in a non-equal way and displays the final plot result according to the size of the plot area.

1. The Syntax Of Function subplot2grid().

1. The subplot2grid() function syntax is plt.subplot2grid(shape, location, rowspan, colspan), below is the input parameters introduction.
2. shape: The grid region specified by this parameter value is used as the drawing region.
3. location: Draw the graph at the given location, the initial position (0,0) representing row 1, column 1.
4. rowsapan/colspan: These two parameters are used to set how many rows and columns the subarea spans.

2. Function subplot2grid() Example.

1. This example adds subareas with different row and column spans to the canvas (figure), and then draws different shapes on each sub-drawing area, below is the example source code.

   # import the matplotlib.pyplot module.
   import matplotlib.pyplot as plt
   
   import numpy as np
   
   def subplot2grid_example():
       
       # create 3 sub areas, the parent area has been divided into 3 rows and 3 columns.
       
       # create the first sub area that span 2 rows and 3 columns, it is located at the (0,0) which means the first row and first column.
       a1 = plt.subplot2grid((3,3),(0,0),colspan = 3, rowspan = 2)
       
       # create the second sub area that span 1 row and 2 columns, it is located at the (2, 0) which means the third row and first column.
       a2 = plt.subplot2grid((3,3),(2,0), rowspan = 1, colspan = 2)
       
       # create the third sub area that span 1 row and 1 column, it is located at the (2,2) which means the third row and third column. 
       a3 = plt.subplot2grid((3,3),(2,2),rowspan = 1, colspan = 1)
   
       # create a number array.
       x = np.arange(1,10)
       print(x)
       
       # plot the square curve on the first sub area.
       a1.plot(x, x*x)
       a1.set_title('square')
       
       # plot the exp curve on the second sub area.
       a2.set_title('exp')
       a2.plot(x, np.exp(x))
       
       # plot the log curve on the second sub area.
       a3.plot(x, np.log(x))
       a3.set_title('log')
       
       # adjust the sub plots paddings. 
       plt.tight_layout()
       
       plt.show()     
       
   if __name__ == '__main__':
       
       subplot2grid_example()

2. When you run the above source code, you can get the below picture.