How to Use Subplot in MATLAB: Syntax and Examples

Use subplot(m, n, p) in MATLAB to divide the figure into an m by n grid and place the plot in the p-th position. This lets you display multiple plots in one window easily.

Syntax

The subplot function divides the figure window into a grid of m rows and n columns. The third argument p specifies the position of the current plot in this grid, counted column-wise from left to right, top to bottom.

• m: Number of rows in the grid
• n: Number of columns in the grid
• p: Position index of the subplot (1 to m*n)

matlab

subplot(m, n, p)

Example

This example creates a figure with 2 rows and 2 columns of plots. Each subplot shows a simple plot with different data.

matlab

x = 1:10;

subplot(2, 2, 1)
plot(x, x)
title('Plot 1: y = x')

subplot(2, 2, 2)
plot(x, x.^2)
title('Plot 2: y = x^2')

subplot(2, 2, 3)
plot(x, sqrt(x))
title('Plot 3: y = sqrt(x)')

subplot(2, 2, 4)
plot(x, log(x))
title('Plot 4: y = log(x)')

Output

A figure window opens showing 4 plots arranged in a 2x2 grid with titles as described.

Common Pitfalls

Common mistakes when using subplot include:

• Using a p value larger than m*n, which causes an error.
• Not calling subplot before each plot, which overwrites the previous plot.
• Confusing the order of m, n, and p.

Always specify subplot before plotting to place the plot in the correct grid cell.

matlab

subplot(2, 2, 5) % Wrong: position 5 does not exist in 2x2 grid
plot(1:10)

% Correct way:
subplot(2, 2, 1)
plot(1:10)

Output

Error: Index exceeds matrix dimensions for the first plot command; second plot displays normally in first subplot.

Quick Reference

Function	Description
subplot(m, n, p)	Create a grid of m rows and n columns, activate p-th subplot
plot(x, y)	Plot data in the current subplot
title('text')	Add title to the current subplot
clf	Clear current figure window
figure	Create new figure window

Key Takeaways

Use subplot(m, n, p) to divide the figure into a grid and select the plot position.

Always call subplot before plotting to avoid overwriting plots.

The position p counts left to right, top to bottom starting at 1.

Ensure p does not exceed m*n to prevent errors.

Use titles and labels to clearly identify each subplot.