similar to: Varying as.Date performance

Dear Rs: Hi, I am trying to read a big text file (nrows=243440, ncols=144). It seems the computational time of all the read methods (scan,readtable,read.delim) is not linear to the number of rows I want to read in: things became really slow once I tried to read in 100000 lines compare to 10000 lines). If I am reading the profiling result right, I guess scan wouldn't help either. My

Hello, I am looking for more information about lazy loading introduced in R 2.0.0. Doing ?lazyLoad I got some and there is a 'see also' section that points to 'makeLazyLoading'... But I cannot reach this page. My problem is: I recompiled a library that uses a lot of functions from other libraries (of course I can give details if needed). I load it in my computer: library(svGUI),

Hello there, I am not quite sure how to interpret the output of Rprof (in the following the output I was staring at). I was poking around the web a little bit for documentation but without much success. I guess if I want to figure out what takes so long in my code the 2nd table $by.total and the total.pct column (pct = percent) is the most helpful. What does it mean that [ or [.data.frame is

Hi, I'm running some routines with standard matrix operations like solve() and diag(). When I do a profile, the lead item under total time is standardGeneric(). Furthermore, solve() and diag() have much greater total time than self time. ??? I assume there is some time-consuming decision going on in the usual functions; is there any way to avoid that and go straight to the calculaions? Thanks

Hi, Given a frame with calendar date's: "2005-07-01", "2005-07-02","2005-07-03","2005-07-04","2005-07-05",etc. I want to extract the following from these dates: week number month number year number Any ideas how to accomplish this? Many thanks. Regards, Richard

Hi, Is nchar function knowingly slow in R? I'm doing some string formatting that requires multiple call to nchar, and nchar seems to be very slow. Experiment 1, pass nchar inside sprintf, and it takes 0.7 seconds > system.time(for (i in 1:10000) + str = sprintf('0005%020d', nchar(op)) + )[3] [1] 0.7 Experiment 2, get the length of op separately using nchar, and then pass

it takes a long time to load the lme4 package.anyone else encounter this problem? > system.time(library(lme4)) 佋佖伻侂佇佽佉仾伒伳伋佁伡伃伆侟仯伜Matrix 佋佖伻侂佇佽佉仾伒伳伋佁伡伃伆侟仯伜lattice [1] 19.90 0.30 25.56 NA NA > version _ platform i386-pc-mingw32 arch i386 os mingw32 system i386, mingw32 status Patched major 2 minor

Dear R-list users, I need to use strptime because I have to deal with date with hours and minutes. I read the manual for strptime and I also looked at many examples, but when I try to apply it to my code, I always encounter some problems. I try to change the default format, with no success. Why? How can I change the format? 1. init_day <- as.factor("2015-02-24-00-30")

Dear Jim and dear Enrico, thank you for your replies. Unfortunately your hints didn't solve my problem, and I am getting mad. Can I show you my whole process? I will be as quick as possible. I start from a data frame called Snow of the form year month day hh mm hs 2007 11 19 0 0 0.00 2007 11 19 0 30 0.00 2007 11 19 1 0 0.00 2007 11 19 1 30 0.00 2007 11 19 2 0 0.00 2007 11 19 2 30 0.00 2007 11

Hello, (This is follow up from this thread: http://www.nabble.com/execution-time-of-.packages-td22304833.html but with a different focus) I am often confused by the result of the profiler, when a loop is involved. Consider these two scripts: script1: Rprof( ) x <- numeric( ) for( i in 1:10000){ x <- c( x, rnorm(10) ) } Rprof( NULL ) print( summaryRprof( ) ) script2:

Hi all. I'm developing a function, which must return a square matrix. Here is the code: http://pastebin.com/THzEW9N7 These functions implement an analog of two embedded for cycles. The first variant creates the resulting matrix by columns, cbind()-ing them one by one. The second variant creates the matrix with two columns, which rows contain all possible variants of i and j and calls apply

Hi Stefano, As the help page says: "The default for the format methods is "%Y-%m-%d %H:%M:%S" if any element has a time component which is not midnight, and "%Y-%m-%d" otherwise. This is because when the result is printed, it uses the default format. If you want a specified output representation: format(strptime(init_day, format="%Y-%m-%d-%H-%M"),"%Y-%M-%d

Hi all, I'm using R to find duplicates in a set of 6 files containing Part Number information. Before applying the intersect method to identify the duplicates I need to normalize the P/Ns. Converting the P/N to uppercase if alphanumerical and applying an 18 char long zero padding if numerical. When I apply the pn_formatting function (see code below) to "Part Number" column of the

Hi all, [this is a bit hard to describe, so if my initial description is confusing, please try running my code below] #WHAT I'M TRYING TO DO I'd appreciate any help in trying to speed up some code. I've written a script that converts a matrix of integers (usually between 1-10,000 - these represent allele names) into two new matrices of normally distributed values (representing

I have an R function (about 1000 lines long) that takes more than 20 times as long to run under R Windows 1.9.0 and 1.8.1 than it does under 1.7.1. Profile results indicate that the $<-.data.frame operation is the culprit, but I don't understand exactly what that is (assignment of data frame elements to another variable?), or why it's only a problem under 1.8.1 and 1.9.0. Any advice?

Does anyone know how I can generate a 2x2 table in a format where in each cell of the table, it contains a) count (frequency) b) total percentage c) row percentage d) column percentage. SAS can generate this format easily, is there a R package that can do this? Frequency | Percent | Row Pct | Col Pct | positive negative | Total --------------------------------|------- disease |

R-devel, I'm in the process of choosing a name for a new package. I've already decided that the name will have two parts, 'portfolio' and 'sim', but can't decide between 'portfolioSim' and 'portfolio.sim'. Is there any good reason to choose one over the other? Thanks in advance, Jeff -- Jeff Enos Kane Capital Management jeff at kanecap.com

Any votes for/against? ----- Forwarded message from Rik Faith <faith@alephnull.com> ----- Date: Wed, 28 Nov 2001 12:55:29 -0500 From: Rik Faith <faith@alephnull.com> To: mbp@samba.org Subject: rsync patch X-Mailer: VM 6.96; XEmacs 21.1; Linux 2.4.16 (light) Here is a patch that adds rate information (e.g., kB/s) to the --progress display. I just noticed that 2.4.7pre4 is coming

Dear all, I'm trying to create a virtual S4 class with some subclasses. I noticed that adding slots to this class increases the memory use and slows the functions down. Note that I'm adding very small slots (integer or character both of length 1). I've made a reproducible example at https://github.com/ThierryO/testvirtualclass. The R CMD check --as-cran fails on the tests. Some of

R-devel, I'm interested in looking at some examples of existing R packages that rely heavily on S4 classes to get a feel for varying styles and package organization techniques. Could you recommend any packages that might serve as a good starting point? Thanks in advance, Jeff