MATLAB Programming

Working with M-Files
[m,n] = size(x);
if (~((m == 1) | (n == 1)) | (m == 1 & n == 1)) % Flow control
error('Input must be a vector') % Error message display
end
y = sum(x)/length(x);
% Computation and assignment
Comments
As mentioned earlier, comment lines begin with a percent sign (%). Comment
lines can appear anywhere in an M-file, and you can append comments to the
end of a line of code. For example,
% Add up all the vector elements.
y = sum(x)
% Use the sum function.
In addition to comment lines, you can insert blank lines anywhere in an
M-file. Blank lines are ignored. However, a blank line can indicate the end
of the help text entry for an M-file.
Block Comments. To write comments that require more than one line, use
the block comment operators, %{ and %}:
%{
This next block of code checks the number of inputs
passed in, makes sure that each input is a valid data
type, and then branches to start processing the data.
%}
Note The %{ and %} operators must appear alone on the lines that
immediately precede and follow the block of help text. Do not include any
other text on these lines.
Creating a Simple M-File
You create M-files using a text editor. MATLAB provides a built-in editor, but
you can use any text editor you like. Once you have written and saved the
M-file, you can run the program as you would any other MATLAB function
or command.
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