Susan Margulies science forum beginner
Joined: 28 Jun 2006
Posts: 4

Posted: Thu Jun 29, 2006 1:15 am Post subject:
Solving a largescale sparse almost binary linear system exactly?



Hello, everyone! I am hoping that someone has stumbled across this problem before.
I have a largescale sparse underdetermined binary system (actually, it consists of 1s, 0s, and 1s), and I would like to solve it exactly (meaning a rational solution).
Of course, I have tried Maple, but it is just too slow, as I am dealing with matrices that are 1/2 million by 1/2 million or so.
I know this is going to be a bit of a bear... is there anything that will make it easier? I think most of the libraries like SPARSKIT and UMFPACK solve the linear system by returning the leastsquares optimization, and that is not what I need.
Even if someone could suggest an algorithm that I could modify in an existing library as a starting point, that would be great.
Thanks for anything!
Susan 
