search for: murtas

Dear all Why isn'it possible to calculate Mahalanobis distances with R for a matrix with 1 row (observations) more than the number of columns (variables)? > mydata <- matrix(runif(12,-5,5), 4, 3) > mahalanobis(x=mydata, center=apply(mydata,2,mean), cov=var(mydata)) [1] 2.25 2.25 2.25 2.25 > mydata <- matrix(runif(420,-5,5), 21, 20) > mahalanobis(x=mydata,

I have just uploaded a package to CRAN called `gpclib' for clipping large and complex polygons. This package provides an R interface to Alan Murta's very fast General Polygon Clipper library (written in C), which has an optimized version of the Vatti algorithm. Not all features of Murta's library are implemented -- right now you can do intersections, differences, and unions. There

I have just uploaded a package to CRAN called `gpclib' for clipping large and complex polygons. This package provides an R interface to Alan Murta's very fast General Polygon Clipper library (written in C), which has an optimized version of the Vatti algorithm. Not all features of Murta's library are implemented -- right now you can do intersections, differences, and unions. There

Hi all, i have a dataset of 3D coordinates and can't figure out how to' tell R which One Are the individuals: I have 3 columns which i named x,y and z And then i have 2607 Lines, but each specimen is 33 Lines (79 specimens) How can i tell R to' categorize individuals every 33 Lines? Thanks in advance

If you look at the structure, you'll see: > x$V4 <- 0 > str(x) `data.frame': 4 obs. of 4 variables: $ V1: int 1 2 3 4 $ V2: int 5 6 7 8 $ V3: int 9 10 11 12 $ V4: num 0 Don't know if this is the intended result. In any case, you're probably better off using data.matrix, as > data.matrix(x) V1 V2 V3 V4 1 1 5 9 0 2 2 6 10 0 3 3 7 11 0 4 4 8 12

...32586 2 ind2 28.32586 29.32586 27.32586 28.32586 29.32586 2 ind3 29.32586 27.32586 28.32586 29.32586 27.32586 1 ind4 27.32586 28.32586 29.32586 27.32586 28.32586 1 > ------------------------------------------------------------------------------------------------------ Thanks in advance Fabio Murtas fabio.murtas at gmail.com Nothing in biology make sense if not in Evolution light

On Tue, 03 Oct 2000 10:55:28 +0000, Alberto Murta <amurta at ipimar.pt> wrote: > And objectively, it's a fact that "<-" >makes the code easier to read than "_". I don't follow this argument. Underscore isn't used anywhere else in the language, so when you see one, you know it's an assignment. On the other hand, both "<" and

I expected that something like > for(i in names(my.data.frame)){j <- as.name(i); print(my.data.frame$j)} should work in R (and S). There's always the possibility of using > for(i in names(my.data.frame)){print(my.data.frame[,i])} but can someone someone tell me why doesn't the 1st option work also? Thanks Alberto -- Alberto G. Murta

> Date: Tue, 03 Oct 2000 14:45:32 +0000 > From: Alberto Murta <amurta at ipimar.pt> > > Duncan Murdoch wrote: > > > I don't follow this argument. Underscore isn't used anywhere else in > > the language, so when you see one, you know it's an assignment. On > > the other hand, both "<" and "-" have multiple other uses.

Dear all I was writing some code that needed functions from packages 'MASS' and 'CircStats', and I received a warning saying that the function 'eqscplot' in one of the packages was masked by another 'eqscplot' from the other package (in fact 'eqscplot' from 'CircStats' seems a short version of 'eqscplot' from 'MASS'). This masking of

Hi I have written a small function to calculate distances between pairs of landmarks ('my.dist' bellow). I gave it to a colleague that works with MSWindows and the function doesn't give the right answer: R 1.4.1 for Linux: > my.dist() [1] 22 561 R 1.4.1 for Windows: > my.dist() [1] 22 560 Warning message: Replacement length not a multiple of the elements to replace in

Dear all I have tried to estimate the confidence intervals for predicted values of a nonlinear model fitted with nls. The function predict gives the predicted values and the lower and upper limits of the prediction, when the class of the object is lm or glm. When the object is derived from nls, the function predict (or predict.nls) gives only the predicted values. The se.fit and interval aguments

Hello, I' m trying to change the formula in the rpart function. The format of a general formula is Answer ~ expression, where Answer is the dependent variable and expression is set of terms containing the independent variables and separated by operators. I want the response of the formula is more than one dependent variable. It is possible?

Se ha borrado un texto insertado con un juego de caracteres sin especificar... Nombre: no disponible Url: https://stat.ethz.ch/pipermail/r-help/attachments/20070828/6641b572/attachment.pl

> From: dmurdoch at pair.com (Duncan Murdoch) > Date: Tue, 03 Oct 2000 12:31:32 GMT > > On Tue, 03 Oct 2000 10:55:28 +0000, Alberto Murta <amurta at ipimar.pt> > wrote: > > > And objectively, it's a fact that "<-" > >makes the code easier to read than "_". > > I don't follow this argument. Underscore isn't used

Dear all, 1. How can I compute the intersecting area between 2 polygons ? 2. I have polygons with coordinates in decimal degrees (i.e. 13 deg 30 min = 13.5 decimal degrees). I want to compute their area and get the results in square meters or square kiometers. Can anyone give me a conversion coefficient or a pointer where I can find this information (sorry for this off topic question) ? Thanks

From: Peter Dalgaard > > <davidek at zla-ryba.cz> writes: > > > Dear all, > > > > I read.table a 17MB tabulator separated table with 483 > > variables(mostly numeric) and 15000 observations into R. > This takes a > > few seconds with R 2.3.1 on windows 2000, but it takes > several minutes > > on my Linux machine. The linux machine is

I haven't found a function that directly calculates the matrix inverse, does it exist? Otherwise what would be the fastest way to do it? Patrik Waldmann -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the

Dear R users, I want to share my joy with you. Please see the following excellent introduction to R "Statistiques avec R " by Vincent Zoonekynd http://zoonek2.free.fr/UNIX/48_R/all.html In paticular, you can see a lot of fascinating graphics examples of R from which you can get many hints. Soryy if this is already well-known, but the CRAN search did not show nothing with the keyword

Readers of this list might be interested in the following commenta about R. In a recent report, by Michael N. Mitchell http://www.ats.ucla.edu/stat/technicalreports/ says about R: "Perhaps the most notable exception to this discussion is R, a language for statistical computing and graphics. R is free to download under the terms of the GNU General Public License (see http://www.r-project.