1) Is m sparse? 2) Once you have computed "inverse", what are you going to do with it?
On 10/04/2015 10:31 PM, go canal wrote: > 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 > <[email protected]> wrote: > > > This should be done with a matrix solver indeed!!! > > > > On Oct 4, 2015 11:53 AM, "Ted Dunning" <[email protected]> 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 <[email protected]> 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 < > [email protected]> 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 <[email protected]> > 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 >>> >>> > > > >
