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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] Sparse -- Diagonal product
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Wed, 20 May 2009 14:20:31 +0200
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Aaahh forget _all_ of what I said!
I misread your email -- thought that you were talking about diagonal
matrices evaluating to dense matrices in Core/.
Only take into account Gael's answer :)
Benoit
2009/5/20 Benoit Jacob <jacob.benoit.1@xxxxxxxxx>:
> Actually I am just working on this at the moment (see recent threads
> on diagonal matrices).
> As Gael said this is changing.
> Normally I'd happily let you handle this but this one is really
> tightly integrated with several other core issues.
>
> Cheers,
> Benoit
>
> 2009/5/20 Justin Carlson <justinca@xxxxxxxxxx>:
>> I was a bit surprised today to figure out that Eigen current evaluates
>> the product of a diagonal matrix with a sparse matrix as a dense
>> matrix.
>>
>> Is this intentional? Changing the result to be sparse (which seems
>> sane to me, particularly given my current usage of the library) seems
>> like the right thing to do, but it would represent an API change.
>>
>> Is there a design rationale for this, or is it just that no
>> appropriate specializations have been implemented yet for this case?
>> If there aren't objections to changing the behavior, I'll see about
>> submitting a patch.
>>
>> Thanks,
>> -J
>>
>>
>>
>