Re: FindMinimum var specification
- To: mathgroup at smc.vnet.net
- Subject: [mg8870] Re: [mg8828] FindMinimum var specification
- From: Allan Hayes <hay at haystack.demon.co.uk>
- Date: Tue, 30 Sep 1997 20:16:35 -0400
- Sender: owner-wri-mathgroup at wolfram.com
"Bernd Gehrmann" <gehrmab at uni-muenster.de>
[mg8828] FindMinimum var specification
writes
>why does the following not work (and how can
> I make it work)?
>
> vars := Sequence[{x[1],0.1},{x[2],0.1}];
> FindMinimum[x[1]^2 + x[2]^2, vars];
Explanation: FindMinimum has attribute HoldAll and seems to be
checking input before evaluating vars.
Solution: make it evaluate vars.
vars := Sequence[{x[1],0.1},{x[2],0.1}]
FindMinimum[x[1]^2 + x[2]^2,Evaluate[vars]]
FindMinimum::"fmgz": "Encountered a vanishing gradient. The
result returned may not be a minimum; it may be a maximum or
a saddle point."
Out[33]=
{0.,{x[1]->0.,x[2]->0.}}
Allan Hayes
hay at haystack.demon.co.uk
http://www.haystack.demon.co.uk/training.html
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