Does least squares regularization have to be iterative?

[SirTristan]

Does a http://en.wikipedia.org/wiki/Tikhonov_regularization" solution for least squares have to be iteratively solved? Or is there a way to perform regularization via linear algebra, the way linear regression can be done by solving the (X^TX)B=X^Ty normal equations?

 

[SirTristan]

Anyone know if this needs to be iteratively accomplished?

 

[SirTristan]

Might there be someone who has a definitive answer to this issue? On whether regularization can be algebraically solved or not.