# 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.