search for: borchers

...rovide a good paradigm. I would be interested even if it will not be easy to implement such examples in R, e.g. because of the interactive nature of these graphical displays. Please answer to my e-mail address. In case enough interesting material comes up, I will enter a summary here. Hans Werner Borchers ABB Corporate Research

...like 'lattice' and 'ggplot2'. Searching R-help revealed that 'histogram' is spelled 'histogramm' in almost 2% of the time. I now know how to color whole bars, but did not find a solution for this specific kind of visualization. Many thanks in advance, Hans Werner Borchers ---- Hans W. Borchers ABB Corporate Research ----- ---- Hans W. Borchers ABB Corporate Research Germany -- View this message in context: http://www.nabble.com/Histogram-with-colors-according-to-factor-tp18336930p18336930.html Sent from the R help mailing list archive at Nabble.com.

...those running R from an USB stick because otherwise you have to install it on the disk---what maybe you don't want to do---and then copy it over to the stick. I know there are some concerns with R-(D)COM interface and i assume those using it know which versions to install. Thanks Hans Werner Borchers

...xample runs fine on Debian Linux and Mac OS X 32-/64-bit architectures. In my understanding the approach is correct and, as said above, often used in numerical applications. Can someone explain to me why this fails for the Windows 64-bit compiler and what I should use instead. Thanks. Hans Werner Borchers ABB Corporate Research

...tion > tan(pi*x) as x approaches 1/2 are different, +Inf and -Inf, so the limit is > not well defined. Hence the computer function tanpi(1/2) ought to return > Not-a-Number. > > Bill Dunlap > TIBCO Software > wdunlap tibco.com > > On Fri, Sep 9, 2016 at 10:24 AM, Hans W Borchers <hwborchers at gmail.com> > wrote: >> >> As the subject line says, we get different results for tan(pi/2) and >> tanpi(1/2), though this should not be the case: >> >> > tan(pi/2) >> [1] 1.633124e+16 >> >> > tanpi(1/2) >&g...

...w/o good reason. If there is a connection to a bug fix to integrate(), with NEWS item "integrate() reverts to the pre-2.12.0 behaviour. (PR#15219)", then I do not understand what this pre-2.12.0 behavior really means. Thanks for any help or a hint to what shall be changed. Hans W Borchers PS: This kind of tricky definition in function 'fn' has caused some discussion on this list in July 2009. I still think it should be allowed to proceed in this way.

...erform this task using R functions? Even better, is there a free implementation of kd-trees that I could utilize (the one I found did not conform to the ANSI C standard)? Someome pointed to 'spdep' of the R-Sig-Geo project, but 'knearneigh' only accepts 2D data points. Hans Werner Borchers ABB Corporate Research, Germany ________________________________________________________________________ require (class) nearest <- function (X, n, k=3) ## Find k nearest neighbors of X[n, ] in the data frame ## or matrix X, utilizing function knn1 k-times. { N <- nrow(X) # inds co...

Dear List: An e-mail mentioning the r-project.org address and sent to a friend at a German university was considered spam by the local spam filter. Its reasoning: the URL "r-project.org" is blacklisted at uribl.swinog.ch resp. at antispam.imp.ch. I checked the list http://antispam.imp.ch/swinog-uri-rbl.txt [caution: long list] and indeed, there it was. Can anybody explain how or

...MDL principle, the C4.5 approach, etc. I am especially interested in those methods that take a factor as goal target into account for discretizing continuous-valued attributes. Is there an implementation of any one of those methods available in the many libraries available for R ? Hans Werner Borchers ABB Corporate Research -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To:...

As the subject line says, we get different results for tan(pi/2) and tanpi(1/2), though this should not be the case: > tan(pi/2) [1] 1.633124e+16 > tanpi(1/2) [1] NaN Warning message: In tanpi(1/2) : NaNs produced By redefining tanpi with sinpi and cospi, we can get closer: > tanpi <- function(x) sinpi(x) / cospi(x) > tanpi(c(0, 1/2, 1, 3/2, 2))

Hello, I want to do regression or missing value imputation by knn. I searched r-help mailing list. This question was asked in 2005. ksmooth and loess were recommended. But my case is different. I have many predictors (p>20) and I really want try knn with a given k. ksmooth and loess use band width to define neighborhood size. This contrasts to knn's variable band width via fixing a

>>>>> Duncan Murdoch >>>>> on Sun, 26 Mar 2023 12:41:03 -0400 writes: > On 26/03/2023 11:54 a.m., J C Nash wrote: >> A tangential email discussion with Simon U. has >> highlighted a long-standing matter that some tools in the >> base R distribution are outdated, but that so many >> examples and other tools may use

...best estimate. Using finite precision approximations to irrational and other numbers that cannot be stored exactly can have all types of problems at and near certain values, that is why there are many specific functions for calculating in those regions. On Fri, Sep 9, 2016 at 12:55 PM, Hans W Borchers <hwborchers at gmail.com> wrote: > The same argument would hold for tan(pi/2). > I don't say the result 'NaN' is wrong, > but I thought, > tan(pi*x) and tanpi(x) should give the same result. > > Hans Werner > > > On Fri, Sep 9, 2016 at 8:44 PM, William D...

Dear All, I am having trouble in using R function "constrOptim" to do constraint optimization. It seems that "constrOptim" calls function "optim" when it does the optimization, and "optim" allows us to set "method" to be "SANN" if we want to use simulated annealing. In "optim", the function allows us to set gradient to be

ACM Software Copyright and License Agreement I have often seen the use of routines from the ACM Collected Algorithms, i.e. <netlib.org/toms/> (CALGO, or Trans. On Math. Software, TOMS), in Open Source programs, maybe also in some R packages --- and sometimes these programs are distributed under the GPL license, sometimes under proprietary licenses, e.g. in Scilab. The use of these CALGO

I have a set of data frames ds1, ds2, ... each having the same columns and column names: ds1 <- data.frame(x=c(1,2,3,4), y=c(5,6,7,8)) ds1 <- data.frame(x=c(9,10,11,12), y=c(13,14,15,16)) ... and I would like to combine them into just one data frame like ds <- rbind(ds1, ds2, ...) Because there are so many of them, I will have to use a character array nms <-

Hi, I'm quite new to the R-project. I was suggested to look into it because I am trying to solve the "Subset sum" problem", which basically is: Given a set of integers and an integer s, does any non-empty subset sum to s? (See http://en.wikipedia.org/wiki/Subset_sum_problem) I have been searching the web for quite some time now (which is how I eventually discovered that my

Dear All, Hans Borchers and I have been trying to compute "exact" derivatives in R using the idea of complex-step derivatives that Hans has proposed. This is a really, really cool idea. It gives "exact" derivatives with only a minimal effort (same as that involved in computing first-order forward-dif...

For an application in image processing -- using R for statistical purposes -- I need to solve the following task: Given n (e.g. n = 100 or 200) points in the unit square, more or less randomly distributed. Find a rectangle of maximal area within the square that does not contain any of these points in its interior. If a, b are height and width of the rectangel, other constraints may have to be

All, I am looking for an optimization library that does well on something as chaotic as the Schwefel function: schwefel <- function(x) sum(-x * sin(sqrt(abs(x)))) With these guys, not much luck: > optim(c(1,1), schwefel)$value [1] -7.890603 > optim(c(1,1), schwefel, method="SANN", control=list(maxit=10000))$value [1] -28.02825 > optim(c(1,1), schwefel, lower=c(-500,-500),