MATLAB Programming

12 Programming Tips
Files and Filenames
This section covers the following topics:
• “Naming M-files” on page 12-46
• “Paged Output” on page 12-8
• “Passing Filenames as Arguments” on page 12-47
• “Passing Filenames to ASCII Files” on page 12-47
• “Determining Filenames at Run-Time” on page 12-47
• “ReturningtheSizeofaFile”onpage12-47
Naming M-files
M-file names must start with an alphabetic character, may contain any
alphanumeric characters or underscores, and must be no longer than
the maximum allowed M-file name length (returned by the function
namelengthmax).
N = namelengthmax
N =
63
Since variables must obey similar rules, you can use the isvarname function
to check whether a filename (minus its .m file extension) is valid for an M-file.
isvarname mfilename
Naming Other Files
The names of other files that MATLAB interacts with (e.g., MAT, MEX, and
MDL-files) follow the same rules as M-files, but may be of any length.
Depending on your operating system, you may be able to include certain
nonalphanumeric characters in your filenames. Check your operating system
manual for information on valid filename restrictions.
12-46