Search All of the Math Forum:

Views expressed in these public forums are not endorsed by NCTM or The Math Forum.

Notice: We are no longer accepting new posts, but the forums will continue to be readable.

Topic: Orthonormal basis for null space of a matrix with complex and random elements
Replies: 2   Last Post: Jun 17, 2013 1:36 PM

 Messages: [ Previous | Next ]
 Bruno Luong Posts: 9,822 Registered: 7/26/08
Re: Orthonormal basis for null space of a matrix with complex and random elements
Posted: Jun 16, 2013 3:41 AM

"Maya" wrote in message <kphu6n\$il7\$1@newscl01ah.mathworks.com>...
> Hi,
>
> I want to ask how can I find the orthonormal basis for the null space of a matrix whose elements are random and complex? I have tried with null() but I get Empty matrix: 2-by-0.

That might be a correct answer.

It works for me

>> A=rand(2,3)+1i*rand(2,3)

A =

0.6948 + 0.7655i 0.9502 + 0.1869i 0.4387 + 0.4456i
0.3171 + 0.7952i 0.0344 + 0.4898i 0.3816 + 0.6463i

>> A(end+1,:) = rand(1,2)*A

A =

0.6948 + 0.7655i 0.9502 + 0.1869i 0.4387 + 0.4456i
0.3171 + 0.7952i 0.0344 + 0.4898i 0.3816 + 0.6463i
0.7322 + 1.1432i 0.7001 + 0.5022i 0.5992 + 0.8038i

>> null(A)

ans =

-0.6626 + 0.0000i
0.1763 + 0.1934i
0.7001 - 0.0489i

% Bruno

Date Subject Author
6/15/13 Anja
6/16/13 Bruno Luong
6/17/13 Josh Meyer