[Pw_forum] problem with vc-relax

Stefano Baroni baroni at sissa.it
Sat Jan 10 07:19:41 CET 2009


You are right, Tim. One can easily imagine non-quadratic functions  
such that the gradients are smaller far from the minimum that near it.  
A stupid example is a double well close to the maximum. Stefano

On Jan 10, 2009, at 3:46 AM, Timothy Mason wrote:

> 	
> I see this all the time in my vc-relax attempts.   I've wondered if  
> its actually necessary that the gradients always decrease?
>
> If the potential is not quite quadratic around the minimum then i  
> suppose there is no reason to assume that the forces would aways be  
> decreasing.
>
> Tim Mason
> university of missouri St. Louis
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---
Stefano Baroni - SISSA  &  DEMOCRITOS National Simulation Center -  
Trieste
http://www.sissa.it/~baroni / [+39] 040 3787 406 (tel) -528 (fax) /  
stefanobaroni (skype)

La morale est une logique de l'action comme la logique est une morale  
de la pensée - Jean Piaget

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