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Ublas : |
From: Matthias Troyer (troyer_at_[hidden])
Date: 2005-04-26 11:36:17
On Apr 26, 2005, at 4:18 PM, Michael Stevens wrote:
> On Monday 25 April 2005 14:29, Gunter Winkler wrote:
>> Hello,
>>
>> I was looking for an ublas expression, to compute
>>
>> y += D * A * x;
>>
>> where D is a diagonal matrix (stored in a vector of the diagonal
>> elements
>> of D) and A is a sparse matrix.
>
> I have been wishing a vector to diagonal matrix adaptor too. It is
> something I
> need quite regularly.
We also need such an adaptor for a code that we are currently
developing. I also wonder whether both D*A and A*D are implemented
optimally for dense matrices A?
Matthias