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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] triangular solve on the right with transpose
- From: Gael Guennebaud <gael.guennebaud@xxxxxxxxx>
- Date: Tue, 13 Jul 2010 08:44:41 +0200
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Hi Manoj,
note that we already have a block Cholesky solver in the devel branch.
To answer your question:
A = L.triangular<Lower>().solve<OnTheRight>(B);
cheers,
gael
On Tue, Jul 13, 2010 at 12:45 AM, Manoj Rajagopalan <rmanoj@xxxxxxxxx> wrote:
> Hi,
>
> I am writing a block cholesky solver where I have to solve:
>
> A * L^T = B
>
> where L is lower triangular and is known, B is dense and known, and A is
> dense and unknown. All are in double-precision.
>
> What expression would I have to use to solve for A? I could use:
>
> A = (L.solve(B.transpose()).transpose();
>
> But is there a more natural expression, closer to the math? I remember there
> was a discussion sometime back on how to express "solve-on-the-right" etc..
>
> thanks,
> Manoj
>
>
>