MATLAB Programming

12 Programming Tips
AvoidUsingiandjforVariables
MATLAB uses the characters i and j to represent imaginary units. Avoid
using i and j for variable names if you intend to use them in complex
arithmetic.
If you want to create a complex number without using i and j, youcanuse
the complex function.
Avoid Overwriting Variables in Scripts
MATLAB scripts store their variables in a workspace that is shared with
the caller of the script. When called from the command line, they share the
base workspace. When called from a function, they share that function’s
workspace. If you run a script that alters a variable that already exists in the
caller’s workspace, that variable is overwritten by the script.
For more information: See “M-File Scripts” on page 4-18 in the MATLAB
Programming documentation.
Persistent Variables
To get the equivalent of a static variable in MATLAB, use persistent.
When you declare a variable to be persistent within a function, its value is
retained in memory between calls to that function. Unlike global variables,
persistent variables are known only to the function in which they are
declared.
For more information: See “Persistent Variables” on page 3-6 in the
MATLAB Programming documentation.
Protecting Persistent Variables
You can inadvertently clear persistent variables from memory by either
modifying the function in which the variables are defined, or by clearing the
function with one of the following commands:
clear all
clear functions
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