MATLAB C++ Math Library Reference

The mwVarargin and mwVarargout Classes
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MATLAB supports functions that accept a variable number of input arguments
and return a variable number of return values. The C++ Math Library defines
two classes to handle these functions.
• The mwVarargin class
• The mwVarargout class
The mwVarargin Class
MATLAB C++ Math Library functions that take a variable number of input
arguments have one mwVarargin argument followed by 31 additional mwArray
arguments.
• If you pass 32 or fewer arguments, you can ignore the mwVarargin parameter
and simply pass a series of mwArrays as with any other function.
• Ifyouneedtopassmorethan32inputs,youmustconstructanmwVarargin
object and pass it as the mwVarargin parameter.
Constructors
The mwVarargin constructor has the standard varargin parameter list: one
mwVarargin argument followed by 31 additional mwArray arguments. The
mwVarargin constructors can be nested enabling you to pass an unlimited
number of inputs.
The inputs used to construct the mwVarargin argument appear first on the
argument list for the function, followed by the remaining 31 inputs. It is not
necessary to fill out the mwVarargin constructor parameter list. The arguments
can be distributed between the mwVarargin constructor and the remaining 31
arguments.
For example, the library function horzcat() is a varargin function that
demonstrates the standard varargin parameter list. Its function prototype is
mwArray horzcat(const mwVarargin &in1=mwArray::DIN,
const mwArray &in2=mwArray::DIN,
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