similar to: A question on function return

I would like to know whether there is a faster way to do the below operation (updating vec1). My objective is to update the elements of a vector (vec1), where a particular element i is dependent on the previous one. I need to do this on vectors that are 1 million or longer and need to repeat that process several hundred times. The for loop works but is slow. If there is a faster way, please let

Dear all, Without a loop, I would like transform 3 numeric vectors empty of 0/1 of same length Vec1 : transform 1 to A and 0 to "" Vec2 : transform 1 to B and 0 to "" Vec3 : transform 1 to C and 0 to "" to obtain only 1 vector Vec who is the paste of the 3 vectors (Ex : ABC, BC, AC, AB,...) Any idea ? Thank you for your help -- Michel ARNAUD

Hello again, I am having a problem on Regular expression. Let say I have following code: > gsub("[',]", "", "'asd'f") [1] "asdf" This is perfect. However I am having problem if I include "" (i.e. the double quote) in the first argument as the pattern search: > gsub("[',"]", "",

This can be vectorized. Try ix <- seq_along(vec2) S_diff2 <- sapply(seq_len(N1-(N2-1)*ratio_sampling), \(j) sum((vec1[(ix-1)*ratio_sampling+j] - vec2[ix])**2)) On Sun, Jun 16, 2024 at 11:27?AM Laurent Rhelp <laurentRHelp at free.fr> wrote: > > Dear RHelp-list, > > I try to use the package comprehenr to replace a for loop by a list > comprehension. > > I

Dear R-helpers: I have a question related to using do.call to call cbind and get. #the following works vec1 <- c(1,2) vec2 <- c(3,4) ColNameVec <- c('vec1','vec2') mat <- do.call("cbind",lapply(ColNameVec,get)) mat #put code above into a function then it does not work #before doing so, first remove vec1 and vec2 from global environment rm(vec1,vec2) test

Hello. Sorry I am not sure this question should go to llvm or mesa3d-dev mailing list, so I post it to both. I am writing a llvm backend for a modern graphics processor which has a ISA very similar to that of Direct 3D. I am reading the code in Gallium-3D driver in a mesa3d branch, which converts the shader programs (TGSI tokens) to LLVM IR. For the shader instruction also found in LLVM IR,

Dear RHelp-list, ?? I try to use the package comprehenr to replace a for loop by a list comprehension. ?I wrote the code but I certainly miss something because it is very slower compared to the for loops. May you please explain to me why the list comprehension is slower in my case. Here is my example. I do the calculation of the square difference between the values of two vectors vec1 and

I would be more strong on this advice: learn to think in R, rather than thinking in Python, when programming in R. R has atomic vectors... Python does not (until you import a package that implements them). I find that while it is possible to import R thinking into Python, Python programmers seem to object for stylistic reasons even though such thinking speeds up Python also. A key step in that

Is there any built-in way to lexicographically compare two vectors of the same length in R? The textbook algorithm could be coded as follows: lex.cmp <- function (vec1,vec2) { for (j in 1:length(vec1)) { if (vec1[j] < vec2[j]) { return(-1) } if (vec1[j] > vec2[j]) { return(1) } } return(0) } Thanks, Gabriel

Laurent, Thank you for introducing me to a package I did not know existed as I use features like list comprehension in python all the time and could see using it in R now that I know it is available. As to why you see your example as slow, I see you used a fairly complex and nested expression and wonder if it was a better way to go. As you are dealing with an interpreter doing delayed

I'm not sure this list is the right place for this thing. I noticed some erratic behaviour in sammon(). Running sammon on two nearly identical sets of data results in very different results. Below is an example. I create an initial configuration with cmdscale() and store it into 'vec1'. I write this to file, and read it back in again to 'vec2'. According to cor() on the three

Hello Wise Ones... I need a clever way around a problem with findInterval. Consider: vec1 <- 1:10 vec2 <- seq(1, 10, by = 0.1) x1 <- c(2:3) a1 <- findInterval(x1, vec1); a1 # example 1 a2 <- findInterval(x1, vec2); a2 # example 2 In the problem I'm working on, vec* may be either integer or numeric, like vec1 and vec2. I need to remove one or more sections of this vector;

Hello, I'm using the eclat function of the arules package (1.0-6) for the identification of frequent itemsets. I need the tidLists, but if I set in the function tidLists=TRUE R crashes (Windows XP Professional SP3, 32 bit, R version 2.12.1 (2010-12-16), reproducible on two different computers) with two different error messages or non at all. Minimum examples are: library(arules)

I fully agree with Jeff that the best way to use ANY language is to evaluate the language in terms of not just the capabilities it offers but also the philosophy behind what it was created for and how people do things and just grok it and use it mostly in the way intended. I do that with all the languages I learn, whether for computers or humans. Bringing in something you like from another

Hi everyone. I am quite frustrated that this doesn't work, as all the functions within work fine by themselves. I'd also like any pointers to how to avoid 'for' loops in my code. I understand it's less than desirable, but I'm still quite new and use them a lot. I have a few wide datasets (90 to 120) with long column names, each name contains a number of different

Dear R useRs, i try to integrate the following function for many values "integrand" <- function(z) { return(z * z) } i do this with a for-loop for(i in 2:4) { z <- integrate(integrand, i-1, i)$value cat("z", z, "\n") } to speed up the computation for many values i tried vectors in integrate to do this. vec1<-1:3 vec2<-2:4

Simple one, have read and googled, still no luck! I want to create several empty vectors all of the same length. I would like multiple empty vectors (vec1, vec2, vec3) and want to create them all in one line. I've tried vec1,vec2,vec3 <- vector(length=5) and c(vec1,vec2,vec3) <- vector(length=5) and several other attempts but nothing seems to work ... suggestions? Thanks Jim

Try factor(vec2) in your bwplot() call. -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch]On Behalf Of Ernesto Jardim Sent: Friday, July 09, 2004 9:41 AM To: Mailing List R Subject: [R] Problem with bwplot Hi, I'm ploting some box-and-whisker plots with bwplot but I'm not getting any box-and-whiskers ... just dots.

Hi, Try: ?vec1<-c(1,1,1,1,1,1,1,1,1) if(all(vec1==1)) "xxxxxxxxx" else? "yyyyyyyyyyy" #[1] "xxxxxxxxx" ?vec2<-c(rep(1,4),2) ?if(all(vec2==1)) "xxxxxxxxx" else? "yyyyyyyyyyy" #[1] "yyyyyyyyyyy" #or if(length(unique(vec1))==1) "xxxxxxxxx" else? "yyyyyyyyyyy" #[1] "xxxxxxxxx" ? if(length(unique(vec2))==1)

Dear all, Let say I have following data-frame: Dat <- structure(list(dat = c(-0.387795842956327, -0.23270882099043, -0.89528973290562, 0.95857175595512, 1.61680582493783, -1.17738110289352, 0.210601060411423, -0.827369747447338, -0.36896112964414, 0.440288648776096, 1.28018410608809, -0.897113649961341, 0.342216546981718, -1.17288066266219, -1.57994101992621, -0.913655547602414,