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From go canal <goca...@yahoo.com.INVALID>
Subject Re: matrix inversion in plan ?
Date Mon, 05 Oct 2015 02:31:58 GMT
Thank you all, the solver is something like this, am I correct:
Matrix m = ....
Matrix inverse = new QRDecomposition(m).solve(new DiagonalMatrix(1, m.rowSize()));

The problem I have is that the matrix is too big, I need distributed, or out-of-core solution.

 thanks, canal 


     On Monday, October 5, 2015 6:25 AM, Peter Jaumann <peter.jaumann1@gmail.com> wrote:
   

 This should be done with a matrix solver indeed!!!



On Oct 4, 2015 11:53 AM, "Ted Dunning" <ted.dunning@gmail.com> wrote:
>
>
> It is almost certain that starting with an inversion is a serious error.
>
> Are you sure you don't want a matrix solver instead?
>
> Sent from my iPhone
>
> > On Oct 3, 2015, at 20:09, go canal <gocanal@yahoo.com.INVALID> wrote:
> >
> > oh, it is so unfortunate that the first step of my project requires the
inversion of a very large matrix. will have to revert back to scalapack or
MR based solutions I guess.
> >  thanks, canal
> >
> >
> >    On Saturday, October 3, 2015 11:31 PM, Ted Dunning <
ted.dunning@gmail.com> wrote:
> >
> >
> > I doubt seriously that Samsara will support matrix inversion per se. The
> > problem is
> >
> > a) it densifies sparse matrices
> >
> > b) it is much more costly than solving a linear system
> >
> > Samsara is roughly memory based, but different back-ends will try to
spill
> > to disk if necessary.  It is likely that the resulting degradation in
> > performance would be dramatic and thus unacceptable to most users.
> >
> >
> >
> >> On Fri, Oct 2, 2015 at 8:47 PM, go canal <gocanal@yahoo.com.invalid>
wrote:
> >>
> >> HiI saw some distributed matrix functions included in Samsara now.
> >> Wondering if we have a plan to support matrix inversion ?BTW, am I
correct
> >> that it is distributed memory based, not out-of-core ? thanks, canal
> >
> >


  
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