# How to figure out the number of objects in a workspace?

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Stagleton on 9 Aug 2011
I have taken the workspace function whos and assigned it to variable obj. How do I then find the number of objects in the workspace?
I have:
obj = evalin('base','whos');
%then I go into a loop
count=0;
while(true)
count=count+1;
something=obj(count).class;
%do something
end
Is there a way to find length or sizof obj.class?

Sean de Wolski on 9 Aug 2011
a=whos;
nObj = size({a(:).size},2);
clear a; %to keep the same number of objects; also assuming a _wasn't_ a variable before.
Thus instead of calling it 'a', I would probably call it something like:
hjsdkjfdlsw6237
or
['dklsfjldrf' dec2hex(floor(rand*1000000))]

Stagleton on 9 Aug 2011
That works well, but I in addition to clearing a I think also subtracting 1 is important like Arnaud suggests.
Sean de Wolski on 9 Aug 2011
That part isn't clear to me:
clear
a = whos;
length({a.size})
ans =
0
I'd think you might want to add one, since now there is a variable (_a_), actually in this case two variables (_a,ans_)

Arnaud Miege on 9 Aug 2011
How about length(obj)? Note that this will include obj itself, so you may want to subtract 1.
Arnaud

Stagleton on 9 Aug 2011
hmm, that doesn't work for me.
If I have:
obj=whos;
Then how do I find the number of objects in obj.class?
Arnaud Miege on 9 Aug 2011
I don't think you need obj.class. length(obj) with give you the number of object in the workspace + obj itself.