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Ublas :

From: Nizar Khalifa Sallem (nksallem_at_[hidden])
Date: 2008-08-27 07:06:47


manik.s.m_at_[hidden] wrote:
> Code ensures size matching
> the matrix that I have created is a standard matrix, due to the
> algorithm involved in its calculation it so turns out that it is
> symmetric.
> Now I want L factor for this matrix from cholesky. therefore potrf is used
> and triangular_adaptor is used to make the resultant symm_ada (see
> 'sal' in code) Lower triangular.
>
> But what i get from
> triangular_adaptor<matrix<double>,lower> tal(matrix<double>(sal));
> is an adaptor , I on the other hand need a Lower triangular matrix,
> to perform prod()
> I dont want to write a for loop and do this manually,
> I am sure there must ber a way of using this triangular adaptor in
> place of matrix itself.
>
> Thanks,
> Manik
>
>
>
>> ok,
>> so first of all you need to be sure of the sizes I mean your matrix.size2()
>> == vector.size()
>> then triangualr adaptor or any other adaptor aren't meant to be used this
>> way (at least I guess). They are meant to make triangular matrixes or
>> symmetric one behave as standard matrixes so i guess if you try to do
>> prod(matrix, vector) it should work.
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OK,
so in this case matrix_range should be the solution