similar to: faster way?

Displaying 20 results from an estimated 3000 matches similar to: "faster way?"

2007 Nov 20
1
Vectorization/Speed Problem
Hi, I cannot find a 'vectorized' solution to this 'for loop' kind of problem. Do you see a vectorized, fast-running solution? Objective: Take the value of X at each timepoint and calculate the corresponding value of Y. Leading 0's and all 1's for X are assigned to Y; otherwise Y is incremented by the number of 0's adjacent to the last 1. The frequency and
2019 Feb 01
3
nlminb with constraints failing on some platforms
Hello, R 3.5.2 on ubuntu 18.04. sessionInfo() at the end. Works with me, same results, cannot reproduce the error. f <- function(x) sum( log(diff(x)^2+.01) + (x[1]-1)^2 ) opt <- nlminb(rep(0, 10), f, lower=-1, upper=3) str(opt) xhat <- rep(1, 10) all.equal(opt$par, xhat, tol=0) # good: 5.53 e-7 #[1] "Mean relative difference: 5.534757e-07" all.equal(opt$objective,
2006 Aug 30
5
working with summarized data
The data sets I am working with all have a weight variable--e.g., each row doesn't mean 1 observation. With that in mind, nearly all of the graphs and summary statistics are incorrect for my data, because they don't take into account the weight. **** For example "median" is incorrect, as the quantiles aren't calculated with weights: sum( weights[X < median(X)] )
2019 Feb 01
1
nlminb with constraints failing on some platforms
> On 1 Feb 2019, at 10:00, Martin Maechler <maechler at stat.math.ethz.ch> wrote: > > ........ >>> sessionInfo() >> R version 3.5.2 (2018-12-20) >> Platform: x86_64-pc-linux-gnu (64-bit) >> Running under: Scientific Linux release 6.4 (Carbon) > >> Matrix products: default >> BLAS/LAPACK:
2017 Nov 07
2
Using MLE on a somewhat unusual likelihood function
So I am trying to use the mle command (from stats4 package) to estimate a number of parameters using data but it keeps throwing up this error message: Error in solve.default(oout$hessian) : Lapack routine dgesv: system is exactly singular: U[1,1] = 0 This error sometimes indicates that the list of starting values is too far from optimum but this is unlikely since I picked values close to where
2019 Jan 31
1
nlminb with constraints failing on some platforms
Prof Nash, Prof Galanos Is it possible to use a generic code stub in front of packages that use optimx to improve optimx use or curtail it according to the requirements? Best Regards Amit +91 7899381263 ________________________________________________________________________ Please request Skype as available 5th Year FPM (Ph.D.) in Finance and Accounting Area Indian Institute
2019 Jan 28
8
nlminb with constraints failing on some platforms
I've noticed unstable behavior of nlminb on some Linux systems. The problem can be reproduced by compiling R-3.5.2 using gcc-8.2 and running the following snippet: f <- function(x) sum( log(diff(x)^2+.01) + (x[1]-1)^2 ) opt <- nlminb(rep(0, 10), f, lower=-1, upper=3) xhat <- rep(1, 10) abs( opt$objective - f(xhat) ) < 1e-4 ## Must be TRUE The example works perfectly when
2019 Feb 04
2
nlminb with constraints failing on some platforms
I get the failure message. To be specific: adcomp.git>R CMD BATCH --quiet test_nlminb.R adcomp.git>cat test_nlminb.Rout > f <- function(x) sum( log(diff(x)^2+.01) + (x[1]-1)^2 ) > opt <- nlminb(rep(0, 10), f, lower=-1, upper=3) > xhat <- rep(1, 10) > abs( opt$objective - f(xhat) ) < 1e-4? ## Must be TRUE [1] FALSE My system is described by: adcomp.git>uname
2006 Jun 09
1
Saving dns2.plot as a jpg image
Hello, I am using R 2.2.1 with sn 0.4.0 and am trying to save a dns2.plot as a jpg file. Here is the latest version of the code I have tried: x <- seq(0,200,length=200) y <- seq(0, 35, length=200) jpeg(filename = "C:/fig1.jpg", width = 5, height = 4,pointsize = 12, quality = 100, bg = "white", res = NA)
2019 Feb 01
0
nlminb with constraints failing on some platforms
No error on Windows 10, R.3.5.2 patched, Rblas compiled with OpenBLAS 0.20, Rlapack is base. > f <- function(x) sum( log(diff(x)^2+.01) + (x[1]-1)^2 ) > opt <- nlminb(rep(0, 10), f, lower=-1, upper=3) > str(opt) List of 6 $ par : num [1:10] 1 1 1 1 1 ... $ objective : num -41.4 $ convergence: int 0 $ iterations : int 66 $ evaluations: Named int [1:2] 96 830 ..-
2019 Feb 01
0
nlminb with constraints failing on some platforms
>>>>> Kasper Kristensen via R-devel >>>>> on Mon, 28 Jan 2019 08:56:39 +0000 writes: > I've noticed unstable behavior of nlminb on some Linux > systems. The problem can be reproduced by compiling > R-3.5.2 using gcc-8.2 and running the following snippet: > f <- function(x) sum( log(diff(x)^2+.01) + (x[1]-1)^2 ) > opt
2001 May 14
0
followup: lookup function for density(...) objects
Thanks to Ross Ihaka and Bob Wheeler for responding to my earlier question. I looked into the Johnson system functions in SuppDists package. For now, I want to stick with the density(...) estimator, and so still need the variate lookup function. As per Ross' suggestion, I just did a numerical integration on the density object and used approxfun/splinefun to "lookup" the variate
2019 Feb 06
0
nlminb with constraints failing on some platforms
Thank you, Brad (and others), >>>>> Brad Bell on Mon, 4 Feb 2019 07:21:18 -0700 writes: > I get the failure message. To be specific: adcomp.git> R CMD BATCH --quiet test_nlminb.R adcomp.git> cat test_nlminb.Rout >> f <- function(x) sum( log(diff(x)^2+.01) + (x[1]-1)^2 ) >> opt <- nlminb(rep(0, 10), f, lower=-1, upper=3) >>
2019 Jan 31
0
nlminb with constraints failing on some platforms
This is not about the failure on some platforms, which is an important issue. However, what is below may provide a temporary workaround until the source of the problem is uncovered. FWIW, the problem seems fairly straightforward for most optimizers at my disposal in the R-forge (developmental) version of the optimx package at https://r-forge.r-project.org/projects/optimizer/ I used the code ##
2017 Nov 07
0
Using MLE on a somewhat unusual likelihood function
(inline) > On 7 Nov 2017, at 06:02 , Hugo Andr? <karlhugoandre at gmail.com> wrote: > > So I am trying to use the mle command (from stats4 package) to estimate a > number of parameters using data but it keeps throwing up this error message: > > Error in solve.default(oout$hessian) : > Lapack routine dgesv: system is exactly singular: U[1,1] = 0 > > This error
2007 Feb 17
1
Solve in maximum likelihood estimation
Hi, I got the following problem. I am doing a maximum likelihood estimation for a Kalman Filter. For this purpose, I have to invert an error matrix Ffast of dimension "no. parameters X no.parameters". The usualy optim methods often find only local minima, so I decided to make the optimization using the SANN algorithm, which is very slow already. However, this becomes a real problem
2007 Oct 23
1
Compute R2 and Q2 in PLS with pls.pcr package
Dear list I am using the mvr function of the package pls.pcr to compute PLS resgression using a X matrix of gene expression variables and a Y matrix of medical varaibles. I would like to obtain the R2 (sum of squares captured by the model) and Q2 (proportion of total sum of squares captured in leave-one-out cross validation) of the model. I am not sure if there are specific slots in the
2002 Apr 24
3
nonlinear least squares, multiresponse
I'm trying to fit a model to solve a biological problem. There are multiple independent variables, and also there are multiple responses. Each response is a function of all the independent variables, plus a set of parameters. All the responses depend on the same variables and parameters - just the form of the function changes to define each seperate response. Any ideas how I can fit
2013 Feb 05
1
R -HELP REQUEST
Good morning to you all, Sorry for taking your time from your research and teaching schedules.   If you have a non-stationary univariate time Series data that has the transformation: Say; l.dat<-log (series) d.ldat<-diff (l.dat, differences=1) and you fit say arima model. predit.arima<-predict (fit.series, n.ahead=10, xregnew= (n+1) :( n+10)) How could I re-transform
2017 Dec 10
3
[cfe-dev] Who wants faster LLVM/Clang builds?
Hi Michael, On Thu, Dec 7, 2017 at 3:16 AM, Michael Zolotukhin <mzolotukhin at apple.com> wrote: > > Nice to IWYU developers here:) I wonder how hard it would be to run IWYU on > LLVM/Clang (or, if it’s supposed to work, I wonder what I did wrong). There are known problems with running IWYU over LLVM/Clang -- Zachary Turner made an attempt a while back to get it up and running.