[Fwd: How do we find alpha?]

[Jafar Sadjadi]

You may use the function fmin in matlab to find best value of alpha.
How to do it... it is actually part of your assignment..

> From gmo...@interlog.com Wed Feb 11 16:35:18 1998
> From: Graham Mooney <gmo...@interlog.com>
> Reply-To: gmo...@interlog.com
> Organization: Systems Design Engineering
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> Subject: [Fwd: How do we find alpha?]
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> Hi,
>
> I am trying to do the steepest descent method for this week's ssignment
> and I can't figure out how to determine alpha when we have two equations
> ( f(xo - alpha*Gradient(xo)) is a 2x1 matrix). Don't we need some kind
> of initial guess so that we can use Newton's method or something? How do
> we get this initial guess.
>
> Graham Mooney
> P.S. There was a rumour flying around that we could just use alpha=1.
> This does not work as the solution blows up to infinity (alpha=0.25
> works).
> ---------------------------------------------------------------------
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