similar to: Position in a vector of the last value > n

Dear R-Help list: I'm using the Matrix library to operate on 600 X ~5000 element unsymmetrical sparse arrays. So far, so good, but if I find I need more speed or functionality, how hard would it be to utilize other sparse matrix toolsets from within R, say MUMPS, PARDISO or UMFPACK, that do not have explicit R interfaces? More information on these is available here

In the Matrix package v. 0.995-11 I see that the dgTMatrix Class for compressed, sparse, triplet-form matrices handles Identically indexed data instances by summing their values, e.g., library(Matrix) (Mt <- new("dgTMatrix", i = as.integer(c(0,0,1,1,4)), j = as.integer(c(0,1,2,2,4)), x = as.double(1:5), Dim = as.integer(c(5,5)))) ## 5 x 5 sparse Matrix of class

In the Matrix package v. 0.995-11 I see that the dgTMatrix Class for compressed, sparse, triplet-form matrices handles Identically indexed data instances by summing their values, e.g., library(Matrix) (Mt <- new("dgTMatrix", i = as.integer(c(0,0,1,1,4)), j = as.integer(c(0,1,2,2,4)), x = as.double(1:5), Dim = as.integer(c(5,5)))) ## 5 x 5 sparse Matrix of class

Ive been converting elements of matrices and arrays, e.g., from Integers to double-precision, by vectorizing the matrix and then remaking it. Alternatively, I can redefine one element as double which then redefines them all. Both methods are quick, so I guess I shouldn't complain, but I would have thought there'd be something more obvious. Have I missed it? Here's my redimensioning

Hello, The code below is supposed to be a wrapper for matplot to do columnwise visible comparison of several matrices, but I'm doing something wrong because I can't access an argument called 'colnum'. I'd be most grateful for some insight. Thanks, John Thaden Little Rock, AR ################################ # mmatplot is a matplot wrapper to compare the same column of #

## While in R v. 2.3.1 (the mid-July patch for Windows) ## on a Windows XP machine, this call to order() works fine... order(1:10,decreasing = TRUE) ## [1] 10 9 8 7 6 5 4 3 2 1 ## ...however, the argument name 'decreasing' ## must be typed in toto (note the missing 'g' ## in the following): > order(1:10,decreasin = TRUE) ## Error in order(na.last, decreasing, ...) :

I am pretty pleased with baselines I fit to chromatograms using the runquantile() function in caTools(v1.6) when its probs parameter is set to 0.2 and its k parameter to ~1/20th of n (e.g., k ~ 225 for n ~ 4500, where n is time series length). This ignores occasional low- side outliers, and, after baseline subtraction, I can re-adjust any negative values to zero. But runquantile's

Does R, or will R, be integrating the changes to the Chambers/Lucent S language under their version 5.0? If not already, then when? John Thaden Little Rock, Arkansas, USA -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe"

R pattern-matching and replacement functions are vectorized: they can operate on vectors of targets. However, they can only use one pattern and replacement. Here is code to apply a different pattern and replacement for every target. My question: can it be done better? sub2 <- function(pattern, replacement, x) { len <- length(x) if (length(pattern) == 1) pattern <-

Peter Dalgaard BSA <p.dalgaard at biostat.ku.dk> wrote: > Martin Maechler <maechler at stat.math.ethz.ch> writes: [ snip... ] > > >From this logic, coercing to a matrix should coerce to character rather > > than integer/numeric codes. > > Hm. I'm not sure there really is much logic in this... Factors are > sometimes character-like, sometimes

I use the step() function occasionally, and I think I understand its objective, proper use, and limitations. Now I see stepwise model selection being used in what seems to be an unusual way, and I wonder if it is right or wrong. May I describe? Genetic mapping tries to find where in an animal's genome are genetic elements that influence a particular physical trait. Say there are 100

Hi R-experts, I have data from four conditions of an experiment. I tried to create four subsets of the data with read.table, for example, read.table("Experiment.csv",subset=(condition=="1")) . I found a similar post in the archive, but the answer to that post was no. Any new ideas about reading subsets of data with read.table? Thanks! Feng [[alternative HTML version

Let's start with a concrete case of n=3 dimensions. Along dimension x, I have a matrix of 5 vectors (each with ten rows) Along dimension y, I have a matrix of 3 vectors (each with ten rows) Along dimension z, I have a matrix of 2 vectors (each with ten rows) I am trying to write a: function(..., funcp) { } where funcp(...) is an operator which works on n vectors and returns a numeric.

I realize this should be simple but I'm having trouble subsetting vectors and matrices, for example extracting all values meeting a certain criterion, from a vector. Cannot seem to figure out the correct syntax and help page not very helpful. Or should I be using some other function than subset. Thanks for any help. Jim Bouldin

Hello all, How do I actually use the output of predict.lm(..., type="terms") to predict new term values from new response values? I'm a chromatographer trying to use R (2.15.1) for one of the most common calculations in that business: - Given several chromatographic peak areas measured for control samples containing a molecule at known (increasing) concentrations, first

Hi to all, I am just looking for more efficient ways ;-) is there a better way instead a loop to decrease x if greater y test <- c(1,3,5,7,9) decrease if greater 1 to test2 <- c(1,2,4,6,8) Kind regards Knut

I understand that everything passed to an R function is passed "by value". This would seem to include data frames, which my current application uses heavily, both for storing program inputs, and holding intermediate and final results. In trying to get greater performance out of my R code, I am wondering if there is any clean way to access data frames without having them copied all the

Hi, We got a question about interpretating R-suqared. The actual outputs for a test dataset is X=(x1,x2, ..., xn). model 1 predicted the outputs as Y1=(y11,y12,..., y1n) model n predicted the outputs as Y2=(y21,y22,..., y2n) ... model m predicted the outputs as Ym=(ym1,ym2,..., ymn) Now we have two ways to calculate R squared to evaluate the average performance of committee model. (a)

I wasn't sure about the subject so I am sorry about the vagueness, but if I have a vector of values, how do I get a certain type of vectors to be bold or italics? So let x be a vector from -10 to 10, how would I tell it to bold the x values that are greater than 0? Or like absolute value of 5? Is it possible to do this in like an if else statement? Could I use x<-seq(-10,10,1)

Hello, just my opinion, but yesterday I run into a case, where after 7 hours of transferring a file (a little bit greater than 1 GB) the scp reported 100% and after that exited with an error (AIX 7.1): $ tsocks scp foo user at host:/tmp ... 100% 1101MB 44.2KB/s 448.0KB/s 7:05:38 scp: /tmp/foo: File too large Probably it should not be rounded up to 100% ? -- MfG/Sincerely Toralf F?rster