Numerically solving the null vector

1. May 12, 2009

wdlang

i have a 1000 by 1000 matrix A

A is definitely singular

I want to solve the null vector numerically

How to do this?

matlab does not work!

2. May 12, 2009

jbunniii

Can you clarify what you mean by "solve the null vector"? Do you mean that you want to find a vector $$x \neq 0$$ such that $$Ax = 0$$? i.e., to find a nonzero element of the null space?

3. May 12, 2009

wdlang

yes!

4. May 12, 2009

jbunniii

If you want to use Matlab to do it, look up the "null" command:

Z = null(A);

returns an orthonormal basis for the null space of A.