MATLAB Programming

4 M-File Programming
Arguments That Default
Any arguments that you do not include in a call to your function are given
their default values by MATLAB. You defined these default values when you
created your schema using the addOptional and addParamValue methods.
The UsingDefaults property is actually a structure that contains the names
of any arguments that were not passed in the function call, and thus were
assigned default values.
Add the following to your M-file:
% Show which arguments were not specified in the call.
disp(' ')
disp 'List of arguments given default values:'
for k=1:numel(p.UsingDefaults)
field = char(p.UsingDefaults(k));
value = p.Results.(field);
if isempty(value), value = '[]'; end
disp(sprintf(' ''%s'' defaults to %s', field, value))
end
Save the M-file and run it without specifying the format, outputDir, or
maxHeight arguments:
publish_ip('ipscript.m', 'maxWidth', 500);
List of arguments given default values:
'format' defaults to html
'outputDir' defaults to D:\work_r14
'maxHeight' defaults to []
Validating the Input Arguments
When you call your function, MATLAB checks any arguments for which you
have specified a validator function. If the validator finds an error, MATLAB
displays an error message and aborts the function. In the publish function
example, the outputDir argument validates the value passed in using
@ischar.
Pass a number instead of a string for the outputDir argument:
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