MATLAB Programming

Function Arguments
nargin and nargout, on the other hand, are functions and when called within
a nested function, always return the number of arguments passed to or from
the nested function itself.
Using varargin and varargout
varargin or varargout used in a nested function can refer to optional
arguments passed to or from that function, or to optional arguments passed
to or from an outer function.
• If a nested function includes varargin or varargout in its function
declaration line, then the use of varargin or varargout within that
function returns optional arguments passed to or from that function.
• If varargin or varargout are not in the nested function declaration but
are in the declaration of an outer function, then the use of varargin or
varargout within the nested function returns optional arguments passed
to the outer function.
In the example below, function C is nested within function B, and function B is
nested within function A. Thetermvarargin{1} in function B refers to the
second input passed to the primary function A, whilevarargin{1} in function
C refers to the first argument, z, passed from function B:
function x = A(y, varargin)
B(nargin, y * rand(4))
% Primary function A
function B(argsIn, z) % Nested function B
if argsIn >= 2
C(z, varargin{1}, 4.512, 1.729)
end
function C(varargin) % Nested function C
if nargin >= 2
x = varargin{1}
end
end % End nested function C
end % End nested function B
end % End primary function A
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