Re: Sparse Matrix, Memory Allocation

*To*: mathgroup at smc.vnet.net*Subject*: [mg31642] Re: Sparse Matrix, Memory Allocation*From*: "Robert Nowak" <robert.nowak at ims.co.at>*Date*: Fri, 23 Nov 2001 05:46:06 -0500 (EST)*References*: <9t2tnm$6pi$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

look at the mathematica help for SparseLinearSolve SparseLinearSolve[smat, vec] solves a sparse linear system; the matrix smat is represented in the form {{i1,j1}->a1, {i2,j2}->a2,...} so that the element at position ik,jk has value ak and all unspecified elements are taken to be zero. Robert -- --- Robert Nowak (robert.nowak at ims.co.at) IMS Nanofabrication GmbH A-1020 Wien, Schreygasse 3, Austria Phone: (+43 1)2144894-32, Fax: (+43 1)2144894-99 Inkyu Rhee <Inkyu.Rhee at colorado.edu> wrote in message news:9t2tnm$6pi$1 at smc.vnet.net... > I have a 70000 by 70000(or more) banded sparse matrix. > and this matrix will be updated by specific law for 50 loops. > In each loop, I need to linear solution of this. > > My prblems are: > > I could not specify this matrix: > > K=Table[0,{70000},{70000}];(* Initialize the matrix K *) > > when I trying this in my machines ((1) sun:ram 750M, swap 2665M, > (2) window:A800mhz, 128Mb), > machine gives me 'Out of Memory, Exiting'. > How do you specify this matrix efficiently? > > If this works well, I will update these components of matrix > using certain law. Then I need to solve the equations. > > Developer`SparseLinearSolve[K,x] > > I tried this part using 10000 by 10000 instead of 70000. > It also give me 'Out of Memory ...'. > > Thanks for any help, > > I. Rhee >