Exact NullSpace computations
- To: mathgroup at smc.vnet.net
- Subject: [mg90799] Exact NullSpace computations
- From: brey_maastricht at hotmail.com
- Date: Thu, 24 Jul 2008 05:04:35 -0400 (EDT)
Hello, I need to compute the (exact) NullSpace of an mxn complex exact rational matrix M where m>>n (looking at 1766x1425 now). Moreover, M is pretty sparse and I know the dimensions of the nullspace because I am able to do a fast rank computation on M with MatrixRank[M, Modulus->largeprime]. When I simply apply the NullSpace[M] function, the computations take one whole month to finish. I am sure there should be a faster way but I don't have a clue yet. Any suggestions ? Hope you guys can help me ! Best regards, Brey from The Netherlands