Givens Rotation: How to code it?

[DNnetz]

Hello!

I want to code the Givens Rotation in PHP. Could you please help me to do that? It would be nice if you could comment on my following approach:

Matrix A:
1 2 3
0 2 0
4 1 0

The value 4 on position 1,3 should be 0. So I have:
c = Ajj / p
s = Aij / p
p = sgn(Ajj)*sqrt(Ajj^2+Aij^2)

Then I have to do some multiplications, but which?

I hope you can help me. Thanks in advance!

[coopster]

Not a lot of love being shown here for the math functions lately [webmasterworld.com], eh DNnetz? ;) I'm sure it's not because folks don't want to assist, it's just (as I stated in the other thread there) this is a pretty deep topic that involves some analysis. A good mathematician would be a friend to have in a time like this!