similar to: optim question

Displaying 20 results from an estimated 400 matches similar to: "optim question"

2011 Dec 12
1
Detecting typo in function argument
With some chagrin after spending a couple of hours trying to debug a script, I realized I had typed in something like ans<-optimx(start, myfn, mygr, lower<-lo, upper=up) that is, the "<-" rather than "=". The outcome on my machine was a non-obvious error several layers deep in the call stack. For info, optim() seems to stop much more quickly. The error is
2009 May 13
2
[LLVMdev] Loop-carried Dependence
Hi, Does anyone know if there is any existing code I can use to do a loop-carried dependence analysis for LLVM IR programs? I searched the mailing-list archive and it seems like someone planned to implement a loop dependence analysis pass in March. I'm just wondering if this project is ongoing/finished or if there is other projects that may have the code I'm interested in. Thanks!
2009 May 15
0
[LLVMdev] Loop-carried Dependence
Hi Wenhao Jia, On Wed May 13 16:30:36 +0200 2009, Wenhao Jia wrote: > Does anyone know if there is any existing code I can use to do a > loop-carried dependence analysis for LLVM IR programs? I searched the > mailing-list archive and it seems like someone planned to implement a > loop dependence analysis pass in March. I'm just wondering if this > project is ongoing/finished or
2009 Mar 03
1
[LLVMdev] Control Data Flow Graph (CDFG)
Hi, Does anyone know any tool that can help generate a control/data flow graph (CDFG) for LLVM IR programs? The opt -view-cfg and related commands can visualize a program as a control flow graph. But how can I embody data flow information into that graph? Your help will be greatly appreciated! Thanks, Wenhao Jia -------------- next part -------------- An HTML attachment was scrubbed... URL:
2011 Aug 29
3
gradient function in OPTIMX
Dear R users When I use OPTIM with BFGS, I've got a significant result without an error message. However, when I use OPTIMX with BFGS( or spg), I've got the following an error message. ---------------------------------------------------------------------------------------------------- > optimx(par=theta0, fn=obj.fy, gr=gr.fy, method="BFGS", >
2017 Dec 31
1
Order of methods for optimx
Dear R-er, For a non-linear optimisation, I used optim() with BFGS method but it stopped regularly before to reach a true mimimum. It was not a problem with limit of iterations, just a local minimum. I was able sometimes to reach better minimum using several rounds of optim(). Then I moved to optimx() to do the different optim rounds automatically using "Nelder-Mead" and
2011 Aug 13
3
optimization problems
Dear R users I am trying to use OPTIMX(OPTIM) for nonlinear optimization. There is no error in my code but the results are so weird (see below). When I ran via OPTIM, the results are that Initial values are that theta0 = 0.6 1.6 0.6 1.6 0.7. (In fact true vales are 0.5,1.0,0.8,1.2, 0.6.) -------------------------------------------------------------------------------------------- >
2009 Mar 04
1
[LLVMdev] Control Data Flow Graph (CDFG)
Hi John, My project is somewhat inbetween, but closer to the latter. If you are doing something related to synthesis, have you checked xPilot from UCLA? Search "llvm" in this paper <http://www.icims.csl.uiuc.edu/~dchen/xpilot-TechCon2005.pdf> Anyway, thanks for the information! :-) Wenhao On Tue, Mar 3, 2009 at 6:30 AM, <llvmdev-request at cs.uiuc.edu> wrote: > >
2011 Feb 06
1
function optimization
Dear all, this is my first time, and just begin to use R. But I've a question about optimization using optimx library. It could sound stupid by I'm a bit affraid with the problem, because anything I try, anything Error. The procedure was: optimx(par="10,71,1",fn=(Prey*Provisioning)/Risk, control=list("maximize)) well the problem lies in the initial value parameters, again
2011 Nov 29
2
Parameters setting in functions optimization
Good afternoon everybody, I'm quite new in functions optimization on R and, whereas I've read lot's of function descriptions, I'm not sure of the correct settings for function like "optimx" and "nlminb". I'd like to minimize my parameters and the loglikelihood result of the function. My parameters are a mean distance of dispersion and a proportion of
2011 Sep 10
1
control list gotcha
This is mainly a reminder to others developing R packages to be careful not to supply control list items that are not used by the called package. Optimx is a wrapper package that aims to provide a common syntax to a number of existing optimization packages. Recently in extending optimx package I inadvertently introduced a new control for optimx which is NOT in any of the wrapped optimization
2019 Jan 31
1
nlminb with constraints failing on some platforms
Prof Nash, Prof Galanos Is it possible to use a generic code stub in front of packages that use optimx to improve optimx use or curtail it according to the requirements? Best Regards Amit +91 7899381263 ________________________________________________________________________ Please request Skype as available 5th Year FPM (Ph.D.) in Finance and Accounting Area Indian Institute
2016 Oct 09
1
optim(?, method=?L-BFGS-B?) stops with an error
I'll not copy all the previous material on this thread to avoid overload. The summary is that all the methods Spencer has tried have some issues. The bad news: This is not uncommon with optimization methods, in part because the problems are "hard", in part because getting them implemented and linked to an interfacing approach like R is very tedious and prone to omissions and
2016 Oct 08
4
optim(…, method=‘L-BFGS-B’) stops with an error message while violating the lower bound
Hello: The development version of Ecdat on R-Forge contains a vignette in which optim(?, method=?L-BFGS-B?) stops with an error message while violating the lower bound. To see all the details, try the following: install.packages("Ecdat", repos="http://R-Forge.R-project.org") Then do "help(pac=Ecdat)" -> "User guides, package
2016 Oct 08
4
optim(…, method=‘L-BFGS-B’) stops with an error message while violating the lower bound
Hi, Mark et al.: Thanks, Mark. Three comments: 1. Rvmmin was one of the methods I tried after Ravi directed me to optimx. It returned NAs for essentially everything. See my email of this subject stamped 4:43 PM Central time = 21:43 UTC. 2. It would be interesting to know if the current algorithm behind optim and optimx with
2011 Nov 02
1
overly long lines in pdf output of manual from package
In re-factoring my optimx package, I'm finding that the pdf output has some lines that are outside the margins (and there are warnings in R CMD check optimx). Clearly I can fix this by editing the tex file that is generated, but the build infrastructure would still get things wrong in automatic processing. So that gives rise to 3 questions: 1) How do I adjust the DESCRIPTION file to avoid too
2010 Jun 22
1
Subject: Re ZINB by Newton Raphson??
I have not included the previous postings because they came out very strangely on my mail reader. However, the question concerned the choice of minimizer for the zeroinfl() function, which apparently allows any of the current 6 methods of optim() for this purpose. The original poster wanted to use Newton-Raphson. Newton-Raphson (or just Newton for simplicity) is commonly thought to be the
2009 Oct 07
1
[LLVMdev] Use LoopInfo in a non-pass class such as ProfileInfoLoader?
Hi everyone, I'm adding loop profiling to LLVM built-in profiler. I'm just wondering in a class that's not a pass, such as ProfileInfoLoader, how can I get information produced by passes such as LoopInfo and DominatorTree? In other words, ProfileInfoLoader is not a pass, so it can't call AnalysisUsage::addRequired and AnalysisUsage::getAnalysisUsage directly. Then how can it know
2015 Apr 24
3
Title case in DESCRIPTION for package where a word is a function name
On 24.04.2015 22:44, Ben Bolker wrote: > Prof J C Nash (U30A <nashjc <at> uottawa.ca> writes: > >> >> I was preparing a fix for a minor glitch in my optimx package and R CMD >> check gave an error that the title was not in title case. > > [snip] to make Gmane happy ... > >> I have found >> >> A Replacement and Extension of the
2011 Aug 31
1
Gradients in optimx
Hi Reuben, I am puzzled to note that the gradient check in "optimx" does not work for you. Can you send me a reproducible example so that I can figure this out? John - I think the best solution for now is to issue a "warning" rather than an error message, when the numerical gradient is not sufficiently close to the user-specified gradient. Best, Ravi.