Re: [bug #6511] Ambiguous minimisation options -- August 04, 2006 - 17:18

For bug number #6511 at
http://gna.org/bugs/?func=detailitem&item_id=6511, the Hessian takes
precedence over the line search.  Hence supplying the option 'none'
with the Newton line search minimisation should set the algorithm to
an unmodified Hessian.  Supplying 'none' twice will turn off the
Hessian modification and no step length selection (or line search)
will be performed.  Chris, do you think that simply stating this
precedence within the 'minimise()' docstring will cover the issue?
Only Newton minimisation uses both a line search and the Hessian.

Edward


On 8/4/06, Chris MacRaild <NO-REPLY.INVALID-ADDRESS@xxxxxxx> wrote:
> URL:
>   <http://gna.org/bugs/?func=detailitem&item_id=6511>
>
>                  Summary: Ambiguous minimisation options
>                  Project: relax
>             Submitted by: macraild
>             Submitted on: Thursday 08/03/2006 at 14:18
>                 Category: None
>                 Priority: 5 - Normal
>                 Severity: 3 - Normal
>                   Status: None
>                  Privacy: Public
>              Assigned to: None
>          Originator Name:
>         Originator Email:
>              Open/Closed: Open
>                  Release: Repository: 1.2 line
>         Operating System: None
>
>     _______________________________________________________
>
> Details:
>
> When performing Newton minimisation (perhaps other algorithms too?), the
> minimisation option 'none' has ambiguous meaning. In practise it performs a
> minimisation without Hessian modifications, but according to the docs, could
> equally mean with no line-search.
>
>
>
>
>
>
>     _______________________________________________________
>
> Reply to this item at:
>
>   <http://gna.org/bugs/?func=detailitem&item_id=6511>
>
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