Chapter 4: Programming in Matlab - College of the Redwoods

344 Chapter 4 Programming in Matlab
Let’s look at a function m-file that sends two outputs back to the calling
program or Matlab command workspace.
◮ Example 7. Write a function m-file that will compute the area and circumference
of a circle of radius r.
Open the editor and enter the following lines.
function [area,circumference]=area_and_circumference(r)
area=pi*r^2;
circumference=2*pi*r;
Save the file as area_and_circumference.m. Set the radius of a particular
circle at the Matlab prompt.
>> radius=12;
Call the function area_and_circumference with input argument radius and
store the resulting area and circumference in the workspace variables A and C.
>> [A,C]=area_and_circumference(radius)
A =
452.3893
C =
75.3982
Functions return output variables in the order in which they are listed in the
function definition line within the m-file. Thus,
[area,circumference]=area_and_circumference(r)
declares that area will be the first output returned and circumference will be
the second.
It is not required that the calling statement (whether from the command line,
a script, or another function) contain the same number of output variables as
defined by the function m-file. If you specify fewer output variables in the calling
statement than are defined in the function m-file, the output variables in the