similar to: How to subset a matrix?

Dear all, I've run into a question of handling large matrices in R. I'd like to define a 70000*70000 matrix in R on Platform: x86_64-apple-darwin9.8.0/x86_64 (64-bit), but it seems to run out of memory to handle this. Is it due to R memory limiting size or RAM of my laptop? If I use a cluster with larger RAM, will that be able to handle this large matrix in R? Thanks much! Best, Hui

I noticed that nls treats weights as relative and that the absolute size of the weights w in the following script has therefore no influence on the errors of the parameters reported in the summary a<-1 b<-3 x<--100:100 y<-a*x+b yeps<-y+rnorm(length(x),sd=1) w<-rep(1,length(x)) plot(x,yeps) lines(x,y) fit<-nls(yeps~p1*x+p2,start=list(p1=a*1.5,p2=b*1.5),weights=w)

Hello, (Sorry for the repost, i am resending in plain text) I have a function 'ewrap' (see below for definition). It takes 3 expressions and returns another expression e.g. map <- ewrap({ len <- length(r$addon) rhcollect(len,1) }) becomes: expression({ NULL result <- mapply(function(.index, k, r) { { len <- length(r$addon)

hello I want a code which can correct the spelling mistakes as well as grammatical mistakes in the sentences...that is if I am writing following sentence: I want too meet my frnd bt due to hectic shcedule I cant I want output in following way: I want to met my friend but due to hectic schedule I can't. Thanks in advance Shilpa Rai MSc IIT Bomaby -- View this message in context:

Hi, here i have some code... a <-1 b <- b+1 c <- b+a/20 if c >5 { d<- 1 } else { d<- 0 } i want to repeat this code from the 2nd line [b <- b+1] without using loop. Actulay i want to use "*Label *" and call *GoTo* method like in other coding Languages. For eg:- like this, a <-1 *LabelBegin :* b <-

I have photographs of plots that look like so: http://r.789695.n4.nabble.com/file/n4631960/Untitled.jpg I need to divide it up so each circle has an equal area surrounding it. So into 20 equal segments, each of which contains a circle. Quadratcount is not sufficient because if I divide it up into 36 equal quadrats, some quadrats do not contain one of the circles. I'm not even sure how to

Dear R Users: I'm a STATA user converting to R, and I'd like to be to do the following. #Assign var_1 and var_2 a value 10->var1 20->var2 #Now I'd like to print the values of var_1 and var_2 by looping through var_1 and var_2 in such a manner: while(y<3){ print(var_y) y+1->y } In STATA, the "y" appended to " var_" is called the local variable and

Dear All, I have been searching online for help increasing my R code more efficiently for almost a whole day, however, there is no solution to my case. So if anyone could give any clue to solve my problem, I would be very appreciate for you help. Thanks in advance. Here is my issue: My desktop is with i7-950 Quad-core CPU with 24Gb memory, and a NVIDIA GTX 480 graphic card, and I am using a

Hello, Is there a convenient way to import RDF/OWL data into R? I'm interested in importing BioPAX/SBPAX data into R to make them available for a wider audience. One exciting application would be to use pathway data to explain differential microarray measurements by identifying upstream nodes that are likely involved in causing the differences. This could also be used to validate

Hi all, I want to use "which.max" to identify the maximum in a 2D array/matrix and I want "argmin" and return the row and column indices. But "which.max" only works for vector... Is there any convinient way to solve this problem? Thanks a lot! [[alternative HTML version deleted]]

Hello, I have a data.frame > names(popA) [1] "Year" "Series" "Age" "WM" "WF" "HM" "HF" "BM" [9] "BF" "IM" "IF" "AM" "AF" "Yr" how do i loop over a subset of variables in this frame to create a vector of

Hi all, I am trying to play around with the randomForest function for classification. I know its performance is great. I am currently using the default options. It has many options. How do I further tweak the options so that I can make its performance even better? What are the options that are mostly used? Thanks a lot! M [[alternative HTML version deleted]]

Hi all, I am looking for recommendations/pointers about best report generator you think that are currently available? i.e. the package that can help turn console output into nice-looking neat report to send to bosses? thanks a lot! [[alternative HTML version deleted]]

Hi all, What parameter do I normally change in the rpart function? How do I set the "cp" option? Is there a way to read off error rate directly from the "rpart" function for training data; I imagine for testing data I have to apply a "predict", but for training data I guess the error count would be somewhere existing once the "rpart" function is

Is there a data/variable explorer in R? Hi all, I am inspecting a complex variable which has lists inside lists... Is there a data-explorer that can help me view the structure and content of such variables? Thank you! [[alternative HTML version deleted]]

head, tail and fix commands don't really work well if I have large matrix/array for which I would like to be able to scroll up and dow, left and right ... Could anybody please help me? Thanks [[alternative HTML version deleted]]

Hi all, I tended to use rbind, or cbind to force a vector be be deemed as a column or row vector. This is very important if I want to do things like u' * A * u, where u' is a row vector and u is a column vector, regardless of what originall format the "u" is... I want to recast it to column vector or row vector... How can I do that?

Hi all, I am using "locator" to select the points from a scatter plot... This is all fine. But the problem is that the locator only returns the axis values of the selected points. Instead, I would like to get the index of these select points... The axis values are real-values so it's a bit hard for me to directly reverse-engineer the index nubmers.. How to do that? Thank you!

Hi all, Could anybody please recommend some hands-on books on classification, data-mining and machine learning with R? I would like to get a very good understanding of the statistical tools that are used in these areas, while reducing the learning curve. Thank you!

Hi all, After trial and error by myself for a few hours, I decide to ask for your help. I have a training set which is a matrix of size 200 x 2, where the two columns denote each independent variable. I have 200 observations. ----------------- ss=data.frame(trainingSet); result=lm(trainingClass~ss$X1+ss$X2); ----------------- where trainingClass denotes the true classes of the training data.