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From: Hugo on 11 Jun 2010 23:28
Hi. I wanted to know if I can initialize a variable in MATLAB, say var, so I can get the following result:
% size(var)
ans
0 0
%

This question came to my mind when I realized that varargin (variable length input argument list) can actually throw this result!

Many thanks in advance.

PS: Any comment regarding this subject will be greatly appreciated.
From: Hugo on 11 Jun 2010 23:57
Sorry! This was not what I wanted to ask... my apologies...

My question is: if I can initialize a variable, say var, so I can get nothing when I type it in the prompt:
% var
%

(I mean without answer)... as the same way one can get with varargin when its list is empty.

Many thanks in advance.
From: Walter Roberson on 12 Jun 2010 00:07
Hugo wrote:
> Sorry! This was not what I wanted to ask... my apologies...
>
> My question is: if I can initialize a variable, say var, so I can get
> nothing when I type it in the prompt:
> % var
> %
>
> (I mean without answer)... as the same way one can get with varargin
> when its list is empty.


No, there is no way.

The reason that varargin returns nothing at all when you use it at the
command prompt is that varargin.m is a script that contains nothing but
comments, and is thus the same thing as typing a bunch of comments at
the command prompt. varargin used within a routine does not return nothing:

Put the below into testvar.m

function testvar(varargin)
varargin
end

Then at the command prompt,
>> testvar
varargin =
{}
From: Matt Fig on 12 Jun 2010 01:12
I am not sure why you would want to do this, but you could mimic the behavior you want by defining a function instead of a variable. For example:

function A = v()
if nargout
A = 3;
end


Now from the command line:

>> v
>> 5*v
ans =
15
>> v^2
ans =
9
>> v
>>
From: John D'Errico on 12 Jun 2010 04:29
"Hugo " <hresquiveloa(a)gmail.com> wrote in message <huuus4$pup$1(a)fred.mathworks.com>...
> Hi. I wanted to know if I can initialize a variable in MATLAB, say var, so I can get the following result:
> % size(var)
> ans
> 0 0
> %
>
> This question came to my mind when I realized that varargin (variable length input argument list) can actually throw this result!
>
> Many thanks in advance.
>
> PS: Any comment regarding this subject will be greatly appreciated.

Easy, peasy.

A = zeros(0,0);
size(A)
ans =
0 0

HTH,
John
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