Plotting

Basic plotting commands
Specify domain values
Plot
Another example and plotting options
Adjust axes
Add a legend, title, and axis labels
Add a grid and a box around the whole plot

Basic plotting commands

The MATLAB "plot" command is the basis for most two-dimensional plotting and visualization tasks in MATLAB. If you provide a vector of data, the plot will index your values as 1, 2, 3, ...

y = [1:.5:4].^2
plot(y)

y =

    1.0000    2.2500    4.0000    6.2500    9.0000   12.2500   16.0000

Specify domain values

In this example, the domain values are not 1, 2, 3, ... but rather are spaced by 0.5. Once x is defined, the definition of y can be done in terms of x.

x = [1:.5:4]
y = x.^2

x =

    1.0000    1.5000    2.0000    2.5000    3.0000    3.5000    4.0000


y =

    1.0000    2.2500    4.0000    6.2500    9.0000   12.2500   16.0000

Plot

plot(x, y)

Another example and plotting options

This example looks at the function:

The @ operator turns an expression in a variable into a function that takes the variable as its operand. Note: This is not supported in older versions of MATLAB.

x = -10:0.001:10;
f = @(x) x.*sin(x.^2);
y = f(x);
plot(x,y);

Adjust axes

axis([-5 5 -4 4])

Add a legend, title, and axis labels

legend('y = x sin(x^2)') 
title('My Plot') 
xlabel('x') 
ylabel('x sin(x^2)')

Add a grid and a box around the whole plot

grid on
box on

Published with MATLAB^® 7.4

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