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From: "Pekka Kumpulainen" <pekka.nospam.kumpulainen@tut.please.fi>
Newsgroups: comp.soft-sys.matlab
Subject: Re: filtering data problem
Date: Fri, 24 Apr 2009 07:09:03 +0000 (UTC)
Organization: Tampere University of Technology
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"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <gsrmsm$5pv$1@fred.mathworks.com>...
> "Pekka Kumpulainen" <pekka.nospam.kumpulainen@tut.please.fi> wrote in message <gsp87p$cdu$1@fred.mathworks.com>...
> > "Jos " <#10584@fileexchange.com> wrote in message <gsp1tf$bno$1@fred.mathworks.com>...
> 
> > 
> > Does enybody know what really happens in this kind of loop?
> > Each time when  an element is removed (assigned to empty), does MATLAB have to find a new contiguous memory block for the new slightly smaller array? Thus fragmenting memory. 
> 
> Yes it does (Using my own PrintPtr mex command to track data pointer):
> 
> >> a=[1:10]
> a =
>      1     2     3     4     5     6     7     8     9    10
> 
> >> PrintPtr(a)
> Ptr=0E23B720x
>  
> >> a(1)=[]
> a =
>      2     3     4     5     6     7     8     9    10
> 
> >> PrintPtr(a)
> Ptr=0E3F1790x % <- it changes
> 
> Bruno

Just what I thought, thanks.
Would that PrintPtr be available? It would be handy sometimes to see what actually happens in the memory.