similar to: How many records could I store in a dataframe?

Hi all, I am doing some intensive computation right now. My system is Pentium4 3.20G + 1.0G RAM + WindowsXP + R1.9.1. It seems my computer is very powerful. However, when I do some simple matrix algebra operations based on a matrix (DD) with dimension 5000000 by 2, I found that the consumption of RAM is huge. For example, the command a <- 1 - DD[,2] eats my 100M RAM. Does anyone know how

Thanks David first. Probably, David misunderstood my points. source vector = (1,2) the length of the target vector = 3 My expected "complete" outputs should be: 111, 112, 121, 122, 211, 212, 221, 222. sample(c(1,2),3,replace=TRUE) just gives me one "randomly sampled" combination at a time. However, I need the whole list displayed above at a time. Rui

Hi all, I try to create an import library for using dll. Following the instruction in the readme.package, I used the command “lib /def:R.exp /out:Rdll.lib”, however, the error message showed “Cannot open file R.exp”. I downloaded the source code R-1.9.0.tgz, but I can not find R.exp. Thanks! Rui Phone: (403)220-4501 Email: rwang@math.ucalgary.ca Department of Mathematics and Statistics

Hi, I am trying to remove a series of records from a large dataframe. The script I have written works fine but takes a long time to run. Can anyone suggest a quicker way to do this? Here is an example of the code I've written. The end result of this bit of code would be a dataframe with any records relating to ID 1 or ID 4 removed: #dataframe id <- c(1,1,1,1,2,2,2,2,2, 3,3,3, 4,4)

Hi folks, I tried to use Mirosoft Fortran Powerstation 4.0 to create a dll file. However, when I used the command dyn.load(“test.dll”), I got the following message: NULL Warning message: DLL attempted to change FPU control word from 9001f to 90003 I read the instruction on Duncan Murdoch’s website about preserving registers, but I still don’t understand it. For example, 1. On first entry

Hi folks, I have a question about how to load a dll. First, I use the command > dyn.load("lassofu.dll"); then, I got the message below “NULL Warning message: DLL attempted to change FPU control word from 9001f to 90003”; After I tried to use this dll in one of s functions, I got the message below “Error in .Fortran("lasso", as.double(x), as.double(y), as.double(b),

Hi Kevin, I think there are issues with Rui's proposed solution. For example, if there are rows in myDF1 which have a studyno which does not match any row in myDF2, then you will lose those rows. In your original request you said that you wanted to keep those rows. To demonstrate my point I need to modify your sample data. Specifically, I changed some studyno settings in myDF1, and also the

?s 22:54 de 11/06/2023, javad bayat escreveu: > Dear Rui; > Many thanks for your email. I used one of your codes, > "data2$LU[which(data2$Layer == "Level 12")] <- "Park"", and it works > correctly for me. > Actually I need to expand the codes so as to consider all "Levels" in the > "Layer" column. There are more than hundred

HI Madhu, I guess you got your solution from Rui: ?dat1<-data.frame(x=c(1,1,2,2,2,3,4,4,4),y=c(23,45,87,46,78,12,87,79,76)) s<-sample(unique(dat1[,1]),length(unique(dat1[,1]))*0.8) ?s #[1] 3 4 2 You can have a list containing both the dataframes list1<-list(dat1[dat1$x%in%s,],dat1[!dat1$x%in%s,]) list1 [[1]] #? x? y #3 2 87 #4 2 46 #5 2 78 #6 3 12 #7 4 87 #8 4 79 #9 4 76 #[[2]] ?# x? y

We have still having problems with Ferret dying on us regularly with the error message: >> ferret server error IO Error occured at <except.c>:93 in xraiseError occured in fs_store.c:127 - fs_each doing ''each'' in /var/www/web1/oms/current/script/../config/../index/production/band/20070805130005: <Too many open files> << We are running Ferret as a

Dear Rui; Many thanks for your email. I used one of your codes, "data2$LU[which(data2$Layer == "Level 12")] <- "Park"", and it works correctly for me. Actually I need to expand the codes so as to consider all "Levels" in the "Layer" column. There are more than hundred levels in the Layer column. If I use your provided code, I have to write it

Dear @Rui Barradas, thank you for the solution. It works perfectly. On 13/10/2017, 23:35, "Rui Barradas" <ruipbarradas at sapo.pt> wrote: Hello, Try the following. myDF1$studyno <- as.character(myDF1$studyno) myDF2$studyno <- as.character(myDF2$studyno) i1 <- which(names(myDF1) == "pf_mcl") merge(myDF1[-i1], myDF2,

Hello, Try the following. myDF1$studyno <- as.character(myDF1$studyno) myDF2$studyno <- as.character(myDF2$studyno) i1 <- which(names(myDF1) == "pf_mcl") merge(myDF1[-i1], myDF2, by = "studyno") Hope this helps, Rui Barradas Em 13-10-2017 20:09, Kevin Wamae escreveu: > I'm trying to populate the column ?pf_mcl? in myDF1 with values from myDF2, where rows

Dear R community, I have two dataframes "first" and "second" which share a unique identifier. I wish to make a new dataframe "third" retaining only the rows in "first" which also occur in "second". I have tried using merge but can't seem to figure it out. Any ideas? Thanks! Mark

I would like to convert a dataframe to an array of lists, one for every record. A natural choide is apply as.list to the rows. However, as it seems, as.list() automatically converts all list elements to the same datatype. Eg: myData <- data.frame(a="foo",b=as.logical(rbinom(10,1,.5))); apply(myData,1,as.list); In this output, all boolean values have been converted to character

Hi , Dataframe Df contains more than 30 no of records.but I want only first 30 rows of data. How can I retrieve it. Thanks K.Ravichandra [[alternative HTML version deleted]]

Dear R-friends, I have to simple questions. First I would like to exclude some columns from a dataframe and after I need select rows that satisfy some conditions. My data frame looks like Region Species Bodysize Weigth Age Africa Sp1 10.2 20 2 Africa Sp2 12.2 12 2 Africa Sp3 15.3 18 3 Africa Sp4 11.5 40 4 Brazil Sp1 10.2 40 3 Brazil Sp2 22.2 32 2 Brazil Sp3 12.3

Hello, This is the sort of question that could interess others, so you should have CCed it to the list. As for the question, from the package vignette, section 3.3.6: "writeWorksheetToFile() is a wrapper function, calling loadWorkbook(), createSheet() and saveWorkbook() functions subsequently. It therefore allows for writing data into worksheets of an Excel file in one call." To

Hi: Suppose that I have a data frame as below x1 x2 x3 ... x10 wk1 wk2 ... Wk208 (these are the column names) For each record, x1, x2, x3 ... x10 are attributes. and wk1, wk2, ..., wk208 are the sales recoreded for this attribute combination. Suppose that now, that I want to do the following 1. Merge the data frame so that I have a new data frame grouped by values of x2 and x3 (for example).

?s 22:50 de 17/10/2024, Sparks, John escreveu: > Hi R Helpers, > > I have been looking for an example of how to execute different dplyr mutate statements on the same dataframe in a single step. I show how to do what I want to do by going from df0 to df1 to df2 to df3 by applying a mutate statement to each dataframe in sequence, but I would like to know if there is a way to execute this