[R] constrained optimisation without second order derivatives? - lnsrch error

2012-04-26 Thread Jonathan Phillips
Hi, I'm trying to do some constrained non-linear optimisation, but my function does not have second order derivatives everywhere. To be a little more specific (the actual function is huge and horrible, so it would probably be better to just describe it) my model has four variables and I'm using op

Re: [R] Constrained Optimisation

2011-12-19 Thread Enrico Schumann
This looks much like the kinds of problems that function 'solve.QP' in package 'quadprog' can handle. But if you want people to help you, follow the posting guide and 'provide commented, minimal, self-contained, reproducible code'. You need to show people what you tried and how it failed (so

Re: [R] Constrained Optimisation

2011-12-19 Thread Florent D.
try the lsei function from the limSolve package. On Mon, Dec 19, 2011 at 2:32 PM, Russell2 wrote: > Dear All > > I have a constrained optimisation problem, I want to maximise the following > function > > t(weights) %*% CovarianceMatrix %*% weights > > for the weights, > > subject to  constraints

[R] Constrained Optimisation

2011-12-19 Thread Russell2
Dear All I have a constrained optimisation problem, I want to maximise the following function t(weights) %*% CovarianceMatrix %*% weights for the weights, subject to constraints on each element within the weights & the weights vector summing to 1. i.e. weights = (x1, x2, x3), where x1 is w

Re: [R] constrained optimisation in R.

2009-07-02 Thread Ravi Varadhan
02, 2009 3:32 PM To: 'Iason Christodoulou' Cc: r-help@r-project.org Subject: Re: [R] constrained optimisation in R. Hi, I know nothing about neither your model nor the Skellam distribution. I will assume that it is a sensible model and that the parameters are identifiable from the data.

Re: [R] constrained optimisation in R.

2009-07-02 Thread Ravi Varadhan
h/People/Faculty_personal_pages/Varadhan.h tml _ From: Iason Christodoulou [mailto:c_iaso...@hotmail.com] Sent: Thursday, July 02, 2009 2:58 PM To: rvarad...@jhmi.edu Subject: RE: [R] constrained optimisation in R. $B&3(Bhe actual problem is: Log ($B&K(

Re: [R] constrained optimisation in R.

2009-07-02 Thread Ravi Varadhan
ursday, July 02, 2009 11:56 AM To: r-help@r-project.org Subject: [R] constrained optimisation in R. i want to estimate parameters with maximum likelihood method with contraints (contant numbers). for example sum(Ai)=0 and sum(Bi)=0 i have done it without the constraints but i realised that i have

[R] constrained optimisation in R.

2009-07-02 Thread Iason Christodoulou
i want to estimate parameters with maximum likelihood method with contraints (contant numbers). for example sum(Ai)=0 and sum(Bi)=0 i have done it without the constraints but i realised that i have to use the contraints. Without constraints(just a part-not complete): skellamreg_LL=function(pa

Re: [R] constrained optimisation

2008-03-15 Thread Paul Smith
On Wed, Mar 12, 2008 at 11:29 AM, giovanna menardi <[EMAIL PROTECTED]> wrote: > i have to optimise a function f(a,b), with a, b vectors in R^d such that a > and b are orthogonal, that is a'b=0. Anybody has a suggestion? And your function f(a,b) is defined by? Paul _

[R] constrained optimisation

2008-03-12 Thread giovanna menardi
Hi, i have to optimise a function f(a,b), with a, b vectors in R^d such that a and b are orthogonal, that is a'b=0. Anybody has a suggestion? Thanks, in advance, for your help, Giovanna _ [[elided Hotmail spam]] [[alte