similar to: efficient filtering of matrices

Hi, I'm having some trouble with a bit of combined C & R code. I'm trying to write a C function to handle the for loops in a function I'm working on to calculate a similarity matrix. Jari Oksanen has kindly added the necessary changes to the vegan package so that I can use the vegdist function, so this isn't absolutely necessary. However, I'm stubborn and want to know

Hi, I'm having some trouble with a bit of combined C & R code. I'm trying to write a C function to handle the for loops in a function I'm working on to calculate a similarity matrix. Jari Oksanen has kindly added the necessary changes to the vegan package so that I can use the vegdist function, so this isn't absolutely necessary. However, I'm stubborn and want to know

Dear R gurus, I have the following code, but I still not know how to estimate and extract confidence intervals (95%CI) from resampling. Thanks! ~Adriana #data penta<-c(770,729,640,486,450,410,400,340,306,283,278,260,253,242,240,229,201,198,190,186,180,170,168,151,150,148,147,125,117,110,107,104,85,83,80,74,70,66,54,46,45,43,40,38,10) x<-log(penta+1) plot(ecdf(x),

Can anyone explain this? I have a matrix with double components. It's taking up a lot of memory, so I want to multiply then turn it to integers. I'm pretty certain that there are only 2 decimal places, but I wanted to check by using modulo. E.g. mat = matrix(11:50/100, ncol=4,nrow=10) #Matrix with values out to the hundredths any((mat * 100)%%1!=0) But oddly enough it doesn't work.

Hi all, Suppose we have the following matrix m <- matrix(c(1,2,3,2,1,3,3,1,2), ncol = 3, byrow=T) where in each row each number occurs only once. I'd like to define a permutation, e.g. 1 -> 2, 2 -> 1, 3 -> 3 and apply it to the matrix. Thus, the following matrix should result: m.perm <- matrix(c(2,1,3,1,2,3,3,2,1), ncol = 3, byrow=T) i.e. each 1 should map to 2 and vice

I am trying to get a random matrix based on an original matrix called disperser.mx, with dimensions 30x73 When I write the following code: >scramble = sample (disperser.mx) >newmat = matrix(scramble, nrow=30) I get the following warning message and a very weird matrix with 30 rows but only 3 columns shown below: Warning message: data length [73] is not a sub-multiple or multiple of the

Duncan, Is this expected for x86_64-apple-darwin12 under Xcode 5? Using current llvm/compiler-rt/clang/polly/testsuite with dragonegg 3.4 branch, I see the warnings... % /sw/lib/gcc4.8/bin/gcc-4 -fplugin=/sw/lib/gcc4.8/lib/dragonegg.so -specs=/sw/lib/gcc4.8/lib/integrated-as.specs -fplugin-arg-dragonegg-enable-gcc-optzns -Ofast himenoBMTxpa.c himenoBMTxpa.c: In function ‘main’:

Dear Friends, I have a matrix of size 5000 X 20. The first two columns are indicator variables taking the value of either 0 or 1. Let us call the first two columns Y1 and Y2. I need to randomly sample 1000 rows with all the associated columns, in other words my new matrix should be of size 1000 X 20. I realize that using this command newmat <- mainmat[sample(1000,replace=F),] achieves

Excuse the simple question... I'm not sure what I'm doing wrong with predict, but let me use this example: Suppose I do: dat<-matrix(c(0,0,10,20),2,byrow=T) lm1<-lm(dat[,2]~dat[,1]) Suppose I want to generate the linearly-interpolated y-values between the point (0,0) and (0,20) at every unit interval. I thought I just do: predict(lm1, data.frame(seq(0,10,1))) to get

I'm looking to create a correlation matrix, but I have already obtained the correlations, which are stored in a vector. (Basically, I'm running a simulation which requires a correlation matrix, but I am simulating the various correlations.) My aim is to create a function that can take the vector, and fit the values into their respective locations in a correlation matrix. (The correlations

On Thu, Nov 21, 2013 at 07:37:46PM -0500, Jack Howarth wrote: > Duncan, > Is this expected for x86_64-apple-darwin12 under Xcode 5? Using current > llvm/compiler-rt/clang/polly/testsuite with dragonegg 3.4 branch, I see > the warnings... > > % /sw/lib/gcc4.8/bin/gcc-4 -fplugin=/sw/lib/gcc4.8/lib/dragonegg.so -specs=/sw/lib/gcc4.8/lib/integrated-as.specs

Hello, I am sure I am not the only person with this problem. I have a list with n elements, each consisting of a single column matrix with different row lengths. Each row has a name ranging from A to E. Here is an example: alph[[1]] A 1 B 2 C 3 D 4 alph[[2]] A 1 C 3 D 4 alph[[3]] A 1 D 4 E 5 I would like to create a matrix from the elements in the list with n columns such that the row names

Hi A toy example is probably the least ambiguous way of explaining what I'm trying to do. > library(ts) > zz<-list(a=rnorm(100),b=rt(100,3)) > zz.spec<-lapply(zz,spectrum,plot=F) > summary(zz.spec) Length Class Mode a 15 spec list b 15 spec list I'm looking for an elegant way to fetch components of the sub-lists a and b of zz.spec; e.g. to make a matrix

I have a dataframe that contains fields such as patid, labdate, labvalue. The same patid may show up in multiple rows because of lab measurements on multiple days. Is there a simple way to obtain just the first and last record for each patient, or do I need to write some code that performs that. Thanks, Steven

Hi folks, I am planning to write some more time-consuming matrix manipulations in c++. What is the experience with the existing c++ matrix libraries? Do you have some recommendations? Are some libraries more compatible with R than the others? All suggestions welcome! Best, Ott

Thank you very much for the example. I think interactively I could get something. But my obstacle is to write an R script that processes my set of data automatically. My difficulty is to extract the information that appears on the screen, when R is operated interactively, from a scripts. Let me go over some steps to make sure I am doing things right. Assume my data have been read into the matrix

I am a beginner and this is a naive question. I have the following data set. row column height 1 2 96 3 7 67 9 25 77 ...... I have a matrix of 50*100 data points and about 60% of them are zeros. I want to put the height data into the matrix according to their row and column numbers. does anybody have experience in setting up such matrix? Your help is highly appreciated. Jack LSU

Dear R list, I have discovered a seemingly peculiar feature when using a matrix to index itself (yes, this is strange code, which I have now modified to be more reasonable). #this makes sense s <- matrix(1:3,nrow=1) s[s] #all three elements are shown #but when I try s <- matrix(1:2,nrow=1) s[1] #fine, the first element is shown s[2] #fine, the second element is

Hi, I have a R output that looks as follow: Rad:0 Rad1:2 Rad3:3 I want to make a new matrix that looks like : sample size is 2400 Variable    n11  n12 Rad            0     2400-0=2400 Rad1          2       2400-2 Rad3  3      2400-3   Thanks a lot for your time and help:) Best,Farnoosh Sheikhi [[alternative HTML version deleted]]

Please excuse what I'm sure are very easy questions but I'm relatively new to the R environment. How can I view a range of list elements, but not all. e.g., I had a matrix of patients and then split them out by patient id. I know I can do patlist[[1]] to see the first one, but how can I view, say, the first ten patients? My other question is how to count how many patients have a