Re: FindMinimum constraints
- To: mathgroup at smc.vnet.net
- Subject: [mg92963] Re: FindMinimum constraints
- From: Jean-Marc Gulliet <jeanmarc.gulliet at gmail.com>
- Date: Tue, 21 Oct 2008 01:44:03 -0400 (EDT)
- Organization: The Open University, Milton Keynes, UK
- References: <gdja4r$idt$1@smc.vnet.net>
dantimatter wrote:
> I have a large and complicated model for which I'm using the
> FindMinimum function to find a solution. The solution consists of 101
> numbers a[i] (i goes from 0 to 100), all greater than zero, and the
> search for each a[i] begins at 0.001:
>
> sol = FindMinimum[{model, Table[a[i] > 0,{i, 0, 100}]}, Table[{a[i],
> 0.001},{i, 0, 100}]];
>
> The line of code that I'm showing here works great. My problem now is
> that I'd like to add an additional constraint: that a[100] ==
> 0.5*(a[0]+a[25]). I can't for the life of me figure out how to
> include this added constraint in the line of code that already works.
> I get errors when I use Append[] to the Table. I would appreciate any
> thoughts on this.
Using *Join* should do the trick. For instance,
sol = FindMinimum[{model,
Join[{a[100] == 0.5*(a[0] + a[25])},
Table[a[i] > 0, {i, 0, 100}]]}, Table[{a[i], 0.001}, {i, 0, 100}]]
Regards,
-- Jean-Marc