Re: using indexed variables in MultiplierMethod[ ], etc.
- To: mathgroup at smc.vnet.net
- Subject: [mg7684] Re: [mg7662] using indexed variables in MultiplierMethod[ ], etc.
- From: Richard Finley <trfin at fiona.umsmed.edu>
- Date: Sun, 29 Jun 1997 22:17:19 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Hi This is one way that should work: u[i_]:=ToExpression["u"<>ToString[i]] will convert your u[i] expressions to ui, that is u[2] will be changed to u2. Hope that helps. RF At 01:36 AM 6/26/97 -0400, you wrote: >I'm not serious programmer in Mma, so please excuse me if this is question is >not stated as clearly as it could be. > >My problem is that I wish to use a Mma package called MultiplierMethod.m which >implements a version of Kuhn-Tucker constrained optimization. The package >defines the function MultiplierMethod[] as follows: > >"MultiplierMethod[f,g,h,x,x0] finds a local solution to a minimization \ >problem where: f is the criterion to be minimized, g is the list (possibly \ >empty) of equality constraints, h is the list (possibly empty) of inequality \ >constraints of the form h(x) <= 0, x = {x1,x2,...} is a generic list of the \ >variables, x0 is an initial vector for x. It returns a list {f*,{x1 -> x1*, \ >etc.}} like FindMinimum. With the option DualParameter -> True it can also \ >provide information on feasibility and Lagrange and/or Karush Kuhn & Tucker \ >multipliers." > >Here's my problem: I'd like to use constraint lists such as >{u[2]-2*u[1]+u[0],u[3]-2*u[2]+u[1],...} which are easily constructed using >Table[], but the MultiplierMehtod package will not accept u[0], u[1], [2], etc. >as variables. It will except u0, u1, u2, etc. as variables, however. Is there >a simple way to get indexed variables such as u[i] to be accepted by packages >such as MultiplierMethod? > >I've already spent an afternoon working on this. Many thanks to anyone who can >help. >