>>>>> Bert Gunter >>>>> on Mon, 17 May 2021 17:27:27 -0700 writes:
> Have you looked here: > https://cran.r-project.org/web/views/Optimization.html yes, he has .. and I've suggested to him to ask here ... > (Warning: I have no idea whether your query even makes > mathematical sense.) Indeed, it *does* make sense; at least for the case of positive (semi-)definite \Sigma which we may well assume for the moment. Martin Maechler > Bert Gunter > "The trouble with having an open mind is that people keep coming along and > sticking things into it." > -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) > On Mon, May 17, 2021 at 12:56 PM Pascal Kündig <pascal.kuen...@bluewin.ch> > wrote: >> Hi everyone, >> I'm looking for an R-function that solves a quadratically constrained >> linear program of the form: >> >> min(x) -\mu' x >> subject to >> x' \Sigma x <= s >> 1'x <= 1 >> -1'x <= -1 >> Ix <= u >> -Ix <= -b >> >> while considering a given starting value for the vector x. >> The above problem results from a larger program of the same structure >> and by setting the constraint that some elements of the solution vector >> \tilde{x} of this larger program have to be 0 if they lie below a >> certain threshold. The starting value for the vector x is therefore a >> subvector of \tilde{x}. \Sigma is symmetric but not necessarily positive >> definite. >> >> ______________________________________________ >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide >> http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. >> > [[alternative HTML version deleted]] > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.