similar to: strange date problem - May 3, 1992 is NA

Hello! I've been trying to get this right for quite a while now and fear there is an easy solution I just don't see. I did not have this problem in Linux, and I searched r-help and Google but did not find a solution, but of course I am grateful for and resources I might not have found our not understood yet. I try to parse a time stamp with time zone. I essentially just want to parse the

Dear R-users, I use unlist of POSIX dates to extract the year, hour etc. With that I can search for files in my database which are in the form 'yyyymmddhh_synops.txt' However, I get stucked during midnight where unlist just gives NA's. The script is given below, the problem accurs at acc.period[16] (midnight). However when I write out the character, unlist works well. But

Under R-2.2.1, a POSIXlt date created with "strptime" has an unknown Daylight Savings Time flag: > strptime(20051208, "%Y%m%d")$isdst [1] -1 This is true on both Linux (details below) and Windows. It did not occur under R-2.1.0. Any ideas? TIA! > Sys.getenv("TZ") TZ "" Version: platform = i686-pc-linux-gnu arch = i686 os = linux-gnu

Delving into the murky world of dates and times I found this: dates <- c("02/27/92", "02/27/92", "01/14/92", "02/28/92", "02/01/92") > times <- c("23:03:20", "22:29:56", "01:03:30", "18:21:03", "16:56:26") > x <- paste(dates, times) > z <- strptime(x, "%m/%d/%y

Hello folks, I found a strangeness while experimenting with POSIXct vectors and lists. It seems that coerced NA's aren't "real" NAs, at least as considered by is.na()? > date_vec = c(as.POSIXct(now()), as.POSIXct(now()+1),NA,"b") > date_vec [1] "2012-08-22 15:00:46 COT" "2012-08-22 15:00:47 COT" NA [4] NA Warning message: In

In trying to use as.Date(), I've come across the conversion of POSIXlt to POSIXct when a POSIXlt variable is included in a data frame: my_POSIX <- strptime(c("11-09-2006", "11-10-2006", "11-11-2006", "11-12-2006", "11-13-2006"), "%m-%d-%Y") str(my_POSIX) my_Date <- as.Date(my_POSIX) str(my_Date) data <- format(my_Date)

Hello all, I am manipulating a large database with 70,000 records. "strptime" generates a date variable but R treats some of the values as NA. I attach a simple example below. I have spent hours on this problem. Any hint would be greatly appreciated. Many thanks, Edwin Sun # =======start of sample code ============= > x <- c("2005-04-02 19:03:00", "2005-04-03

Hi, I have a dataframe column of the form v<-c("Fri Feb 05 20:00:01.43000 2010","Fri Feb 05 20:00:02.274000 2010","Fri Feb 05 20:00:02.274000 2010","Fri Feb 05 20:00:06.34000 2010") I need to convert this to datetime form. I did the following.. lapply(v,function(x){strptime(x, "%a %b %d %H:%M:%OS %Y")}) This gives me a list that looks like

On Windows XP SP3 > format(pippo, format="%I:%M:%S %p") [1] "11:43:12 PM" In any case, if there is a problem it is in Windows, not in R, since this is an Windows service that is being called. So there is no evidence at all of any bug in R here. On Wed, 10 Sep 2008, pego.enrico at tiscali.it wrote: > Full_Name: Enrico Pegoraro > Version: 2.7.2 > OS: Windows

Have you noticed any problems with big dates (>=1/1/2040) in R? Here is the bit of code that I'm having trouble with: > test.date <- strptime("1/1/2040",format="%m/%d/%Y") > > unlist(test.date) sec min hour mday mon year wday yday isdst 0 0 0 1 0 140 0 0 0 > > date.plus.one <- as.POSIXct(test.date) +

Hello, I'm trying to extract the independent variables from a formula. The closest I've been able to come, aside from rolling my own, is the following: > a = y ~ b * x > attr(terms(formula(a)),"variables") The reason I'm doing this is that I'm building a grid of points that I use to construct a 3-d model prediction surface in rgl. If there are more than two

Hello, Suppose we need a function that takes a POSIXct object and need to calculate the time difference between it and GMT time: gmtDiff <- function(time) { time.gmt <- as.POSIXct(format(time, tz="GMT")) time.plt <- as.POSIXlt(time) dlstime <- ifelse(time.plt$isdst > 0, 1, 0) timezone <- as.numeric(difftime(time, time.gmt, units="hours"))

Under platform i686-pc-linux-gnu arch i686 os linux-gnu system i686, linux-gnu status major 1 minor 6.1 year 2002 month 11 day 01 language R > x <- strptime(c('10/10/1969','12/31/2002'),format='%m/%d/%Y')

Hi Guys, I'm cooking up my time series code. I want a data frame with first column as timestamp in POSIXlt format. I hit on this the problem of how to create an array/list/vector of POSIXlt objects. Code is as follows > dtt=array(dim = 2) > t=as.POSIXlt( strptime("07/12/07 13:20:01", "%m/%d/%Y %H:%M:%S",tz="GMT")) > dtt [1] NA NA > t [1]

Hola!! Estoy intentando ejecutar un script com horas, al principio ejecute estos comandos DBx$Date<-strptime(DBx$Date, "%d-%m-%Y") ###Monicap use ; other use Y DBx$Year<-as.POSIXlt(DBx$Date)$year+1900 if(filename!="monicap_50.csv") {DBx$Time<-paste(DBx$Time, ":00", sep="")} Pero me daba el error de que mi base de datos tenia las

I have not used POSIX classes previously and now have a need to use them. I have sports data with times of some athletes after different events. I need to perform some simple analyses using the times. I think I've figured out how to do this. I just want to confirm with others who have more experience that this is indeed the correct approach. If not, please suggest a more appropriate way.

Hi Folks, I'm trying to extract just the backreferences from a regex. > temp = "abcd1234abcd1234" > regmatches(temp, gregexpr("(?:abcd)(1234)", temp)) [[1]] [1] "abcd1234" "abcd1234" What I would like is: [1] "1234" "1234" Note: I know I can just match 1234 here, but the actual example is complicated enough that I have to

Hi list, I have some questions regarding 1) conversion of date + time characters to chron 2) formatting chron object printing Regarding (1), Gabor's Rnews 2004 4/1 article has been indispensible, but I often work with files where dates and times are contained in a single field. In this case, I would like to control input/output of chron objects when each observation of date and time is

Hi folks, I'm trying to figure out how to get summarized data based on multiple columns. However, instead of giving summaries for every combination of categorical columns, I want it for each value of each categorical column regardless of the other columns. I could do this with three different commands, but i'm wondering if there's a more elegant way that I'm missing. Thanks!

Hello, I am an advanced user of R. Recently I found out that apparently I do not fully understand vectors and lists fully Take this code snippet: T = c("02.03.2008 12:23", "03.03.2008 05:54") Times = strptime(T, "%d.%m.%Y %H:%M") Times # OK class(Times) # OK is.list(Times) # sort of understand and not understand that length(Times)