Re: [R] The best solver for non-smooth functions?

2012-07-23 Thread Patrick Burns
There is a new blog post that is pertinent to this question: http://www.portfolioprobe.com/2012/07/23/a-comparison-of-some-heuristic-optimization-methods/ Pat On 18/07/2012 21:00, Cren wrote: # Hi all, # consider the following code (please, run it: # it's fully working and requires just few m

Re: [R] The best solver for non-smooth functions?

2012-07-19 Thread Cren
Roger Koenker-3 wrote > > There are obviously a large variety of non-smooth problems; > for CVAR problems, if by this you mean conditional value at > risk portfolio problems, you can use modern interior point > linear programming methods. Further details are here: > > http://www.econ.uiu

Re: [R] The best solver for non-smooth functions?

2012-07-19 Thread Cren
Hans W Borchers wrote > > The most robust solver for non-smooth functions I know of in R is > Nelder-Mead > in the 'dfoptim' package (that also allows for box constraints). > > First throw out the equality constraint by using c(w1, w1, 1-w1-w2) as > input. > This will enlarge the domain a bit,

Re: [R] The best solver for non-smooth functions?

2012-07-19 Thread Cren
Roger Koenker-3 wrote > > There are obviously a large variety of non-smooth problems; > for CVAR problems, if by this you mean conditional value at > risk portfolio problems, you can use modern interior point > linear programming methods. Further details are here: > > http://www.econ.uiu

Re: [R] The best solver for non-smooth functions?

2012-07-18 Thread Roger Koenker
There are obviously a large variety of non-smooth problems; for CVAR problems, if by this you mean conditional value at risk portfolio problems, you can use modern interior point linear programming methods. Further details are here: http://www.econ.uiuc.edu/~roger/research/risk/risk.html

Re: [R] The best solver for non-smooth functions?

2012-07-18 Thread Hans W Borchers
Cren bancaakros.it> writes: > The most robust solver for non-smooth functions I know of in R is Nelder-Mead in the 'dfoptim' package (that also allows for box constraints). First throw out the equality constraint by using c(w1, w1, 1-w1-w2) as input. This will enlarge the domain a bit, but com

Re: [R] The best solver for non-smooth functions?

2012-07-18 Thread Cren
# Whoops! I have just seen there's a little mistake # in the 'sharpe' function, because I had to use # 'w' array instead of 'ead' in the cm.CVaR function! # This does not change the main features of my, # but you should be aware of it --- # The function to be minimized sharpe <- function(w) {

[R] The best solver for non-smooth functions?

2012-07-18 Thread Cren
# Hi all, # consider the following code (please, run it: # it's fully working and requires just few minutes # to finish): require(CreditMetrics) require(clusterGeneration) install.packages("Rdonlp2", repos= c("http://R-Forge.R-project.org";, getOption("repos"))) install.packages("Rsolnp2", repos=