search for: rnews_2004

R offers a bewildering array of options when it comes to representing dates and times (e.g, as.Date, chron, strptime, zoo, etc). Can anybody recommend a document that compares the relative merit of each method? I'm not looking for help with any one method, but rather a guide that describes which method is best for a particular data analysis/plotting goal. Thanks, Jake [[alternative

...describe it completely, especially in a reader-friendly way. So far I've found: * http://cran.r-project.org/doc/manuals/R-lang.html#Object_002doriented-programming - it has most of the theory (although some bits are missing), but no examples * page 33 of http://CRAN.R-project.org/doc/Rnews/Rnews_2004-1.pdf shows how to create a simple object in both S3 and S4 What has helped you learn S3? Regards, Hadley -- http://had.co.nz/

Full_Name: Mario Luoni Version: 2.10.0 OS: Windows XP HE SP3 Submission from: (NULL) (217.194.59.134) This piece of code: zzz1 <- as.POSIXct("1999-03-18", tz="CET") zzz2 <- as.POSIXlt("1999-03-18", tz="CET") zzz1 == zzz2 as.Date(zzz1) as.Date(zzz2) yields TRUE for "zzz1==zzz2", but the two dates returned by as.Date are different: >

...rtantly, I cannot make chron print the format 12/30/2006 (which my output data requires). I really like the format flexibility of strftime() and strptime(), but of course am paranoid about timezone issues. After reading the standard reference several times (http://cran.r-project.org/doc/Rnews/Rnews_2004-1.pdf), I am tempted to conclude that if I never specify timezones, and never use Sys.time(), the vulnerabilities do not pertain. To the point: if I'm merely converting to and from character data that does not represent time zones, is there still a time zone vulnerability with strftime() a...

Hi, I'm experiencing a problem with strptime. (R 1.9.1 on a Win2000 machine) I have a large list containing 6 columns and 161800 rows. One column contains dates that I want to convert in order to compare the different dates. Some dates work just fine while others become NA. I don't see any difference between the dates. I've attached an example from my code. Hope this explains my

...Windows XP Submission from: (NULL) (207.237.54.242) Hi, I found an arithmetic problem when I'm doing something with POSIXct The code to reproduce it is as follows (This is the recommended way of finding out time zone difference on R News 2004-1 Page 32 URL http://cran.r-project.org/doc/Rnews/Rnews_2004-1.pdf) a=Sys.time() b<-as.POSIXct(format(a,tz="GMT")) a-b unclass(a) unclass(b) unclass(a)-unclass(b) as.numeric(a) as.numeric(b) as.numeric(a)-as.numeric(b) The result on my machine > a=Sys.time() > b<-as.POSIXct(format(a,tz="GMT")) > a-b Time difference of -4...

violating.runs I read from the news cran.r-project.org/doc/Rnews/Rnews_2004-1.pdf that the criteria for the violating is 5 but 1)I cannot find "5" in the code of the function. Where is the "5" ? 2)What is the easiest way to change it ? 3)Is there any more criterias made somewhere ? Yours sincerelly, Tommi Viitanen

Hello, I have large zoo objects (about 100 or more time series merged next to eachother). Example: X05.Oct.99 X05.Nov.99 X05.Dec.99 X05.Jan.00 X05.Feb.00 X05.Mar.00 X05.Apr.00 X05.May.00 X05.Jun.00 [1,] 5649.3 5679.4 5679.4 5679.4 5679.4 5679.4 5679.4 5679.4 5679.4 [2,] 5682.7 5719.2 5719.2 5719.2 5719.2 5719.2 5719.2

Hi all; I've already send a similar e-mail to the list and Prof. Brian Ripley answered me but my doubts remain unresolved. Thanks for the clarification, but perhaps I wasn't clear enough in posting my questions. I've got a postgres database which I read into R. The first column is Timestamp with timezone, and my data are already in UTC format. An 'printed' extract of R

Dear R-users, I'm finding for a R-package concerning graphs. Is there some kind of that package? I've a set of correlation coeffients between several variable and I wish to built a graph to link variables correlated. Many thanks. Best, Vito ===== Diventare costruttori di soluzioni "The business of the statistician is to catalyze the scientific learning process." George

Dear R People: Is there a Quality Control in R book that would be accessible for undergraduates, please? I'm teaching a QC course in the fall semester and would be happy to have a Use R book or something like that, please. Thanks in advance, Erin -- Erin Hodgess Associate Professor Department of Computer and Mathematical Sciences University of Houston - Downtown mailto: erinm.hodgess at

R-help, I have lloked in the archives found no answer to how to round the line joint. I have usedthe arguments lnd, ljoin in par but I get no differences in the plotting. x=1:10 par(ljoin="round",lend="round") plot(x,sin(x),type="l",lwd=2) Any suggestions? I run on a Windows XP machine. > version _ platform i386-pc-mingw32 arch

Dear R users, I have a problem computing time differences using R. I have a date that are given using the following format: 20080620.00, where the 4 first digits represent the year, the next 2 ones the month and the last 2 ones the day. I would need to compute time differences between two vectors of this given format. I tried around trying to change this format into any type of time serie

Hello R List - I have to import Excel files (either as .csv files or using RODBC) into R (2.4.1, Windows) and operate on dates and times (e.g. find minutes between times, change dates to days of week or analyze by weeks of year). The help files for format.Date, strptime, as.POSIX, DateTimeClasses, etc. etc. are informative but perhaps a little terse. I have googled unsuccessfully for a more

Hello all, kind regards, I have imported a data.frame from SPSS using "foreign":read.spss but unfortunately it is reading dates in a way neither R nor myself can understand. > book$DATE [1] 13502246400 13443321600 13477795200 13472956800 13501728000 13445395200 13501382400 13502851200 13444185600 13461465600 13457232000 [12] 13458096000 13432435200 13431484800 13495334400

Dear Reader I am trying to change the font in a plot and after several trials finally came up with the following code. plot(var_a, var_b, pch = 16, font.lab = 10, font = 10) points(var_a, var_c, pch = 3, font = 10) legend(0.1, 0.8, legend = c(?var_b?, ?var_c?), pch = c(16,3)) It does change the font in the plot (Courier), but not in the legend that does not accept the "font = ..."

...at stats.ox.ac.uk, r-help at stat.math.ethz.ch > > I am in a different time zone, EDT, on Windows XP and can't > replicate this but you might try reading the latest R News > article on dates and times for some ideas, viz. page 32 of: > > http://cran.r-project.org/doc/Rnews/Rnews_2004-1.pd > > In particular, try converting them to chron and then doing > your manipulations in chron or else convert them from chron to > POSIXct: > > require(chron) > r.asc <- raincida$ts > r.chron <- chron(substring(r.asc, 1, 10), > substring(r....

Folks, I'm having trouble with how datetime objects with time zones are set and plotted. This may be the result of my running R (2.4.0) on a Windoze XP box. Perhaps not. Here are two example problems I need advise on if you have time: 1) I collect data with dates (often as a fractional day of year) in UTC. Using strptime to create date time objects appears to force the data into

Dear R People: Could someone direct me to some documentation on the difference between S3 and S4 classes, please? For example, why would a person use one as opposed to another? Maybe pros and cons of each? Thanks in advance! R Version 2.2.0 (I'm downloading the new one this afternoon!) Windows. Happy New Year! Sincerely, Erin Hodgess Associate Professor Department of Computer and

Dear R-help I have a problem solving a linear system like 353a+45b+29c=79 45a+29b+3c=5 29a+3b+4c=8 Is there any way of doing this in R? Best Regards Jim ------------------------------------------------------------------------------ This e-mail and any attachment may be confidential and may also be privileged. If you are not the intended recipient, please notify us immediately and then delete