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Subject: Re: curious problem with sparse matrices that have explicit "0" entries.....
Date: Sun, 4 Jan 2009 16:20:03 +0000 (UTC)
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"Tim Davis" <davis@cise.ufl.edu> wrote in message <gjou46$45r$1@fred.mathworks.com>...

> Now, I would argue that it's a pity MATLAB doesn't allow explicit
> zeros (they happen quite naturally, when solving a nonlinear
> system for example).  

But surely the arguments for disallowing them have some substance. It's obviously more storage-efficient. It also allows a more optimal implementation of things like find(). As we've seen, if explicit zeros were allowed, the find() function would need to do additional work to weed out the  indices of explicit zero entries from the final output.