similar to: Add 1 week to date with hours included for subset

Hello there fellow R-users, I have received some data which comes in the following format: example1<-"200301" The first 4 digits correspond to the year and the remaining 2 digits correspond to the week of the year. I have tried to convert this to a date by using strptime as follows: strptime(example1,format="%Y%U") where U (looking up strptime) is the week of the

Hello all, I'm hoping to convert a decimal value for week of the year back to a date object. Eg: strptime(paste(2010,1:52,sep=" "),format="%Y %W") I expected (hoped?) this would give me the date for Monday of each week. Instead, it's giving me 52 values of today's date. Where am I erring? Thanks Michael _______________________________________________________

Hi My data looks like this startDate="2008-06-01" dateRange =c( "2008-10-01","2008-12-01") Is there any method to find the week number from the startDate range ----- Thanks in Advance Arun -- View this message in context: http://r.789695.n4.nabble.com/Week-number-from-a-date-tp4410223p4410223.html Sent from the R help mailing list archive at Nabble.com.

Hello R-users, Does anyone know how obtain the week of a date? (in SPPS the instruction is "xdate.week") Thanks, Juan Ramon -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the

Hi all, Is there a simple function already implemented for getting the ISO weeks of a Date object? I couldn't find one, and so wrote my own function to do it, but would appreciate a pointer to the "default" way. If a function is not yet implemented, could the code below be of interest to submit to CRAN? Best Regards, Gustaf --------------------

Hi, Can strptime (or some other function) help me turn the following column of a data.frame into two new columns, one as date and the other as time, preserving the AM/PM value? Thanks, Mark > B ENTRY DATE 1 3/23/2009 6:30:00 AM 2 3/23/2009 6:30:00 AM 3 3/23/2009 6:39:00 AM 4 3/23/2009 6:39:00 AM 5 3/23/2009 6:48:00 AM 6 3/23/2009 6:48:00 AM 7 3/23/2009 7:00:00 AM

Dear R Community, I am new to R, and have a question that I suspect may be quite simple but is proving a formidable roadblock for me. I have a large data set that includes water-quality measurements collected over many 24-hour periods. The date and time of sample collection are in a combined Date/Time field in the format yyyy-mm-dd hh:mm:ss. I need to be able to subset the data for analysis of

Dear all, I import my data from a csv-file containing one row with date-entries. How can I tell R to treat this data as dates? I've tried to bring it in character-format (as.charachter()) followed by as.POSIXlt() but I get an error message, that the character string is not in a standard unambiguous format, although the date is of format yyyy-mm-dd (what is standard format according to R

> is.na(strptime("5/2/1992", format="%m/%d/%Y")) [1] FALSE > is.na(strptime("5/3/1992", format="%m/%d/%Y")) [1] TRUE Any idea what's going on with this? Running strptime against all dates from around 1946, only 5/3/1992 was converted as "NA". Even stranger, it still seems to have a value associated with it (even though is.na thinks

I used quantmod to pull in price data from the ticker SPY. The data has date and closing price. I would like to show the day of the week for each closing price. Is that possible? Also, I would like to add the back into the data frame in a new column without changing the structure of the data set if possible. SPY 2009-01-02 92.96 2009-01-05 92.85 2009-01-06 93.47

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

I know that this is correct: library(chron) x = dates("01-03-04", format="d-m-y", out.format="day mon year") print(x) It gives me the string "01 Mar 2004" which is correct. I also know that I can say: print(day.of.week(3,1,2004)) in which case he says 1, for today is monday. My question is: How do I combine these two!? :-) I have a

Dear all, I have a question related to the POSIXlt function in R. I have a set of dates and times, for exmaple: startx <- as.POSIXct("2011-01-01 00:00:00") finx <- as.POSIXct("2011-12-31 00:00:00") daysx<- seq(startx, finx, by="24 hours") I want to change the dates of all the days falling on a Saturday to the next working day (i.e. Monday). So I

Dear all, I've come across a problem using strptime, can anyone explain what's going on? I'm using version 2.7.0 on Windows XP. Thank you Caroline First read in a data file using read.table alldata = read.table(file, header=F, skip=4, colClasses = c("character","numeric")) dim(alldata) [1] 223960 2 # inefficient, safe way of sorting out missing or dodgy

Hi list, Could someone explain to me why the following result is not a integer? > difftime(strptime("24NOV2004", format="%d%b%Y"), strptime("13MAY2004", >format="%d%b%Y"), units="days") Time difference of 195.0417 days I'm using R2.12.0 on WinXP. Thanks! ...Tao

Hi, I've been trying to convert numbers from an online temperature database into dates and time that R recognizes. I've tried as.Date, as.POSIXlt and strptime the problem is that the database has put a T between the numbers and R will not accept any conversions. currently it sees the date as a factor with the format as 1981-01-02T08:00I would like to keep only the year and month, but my

Hello, I have a data frame somewhat like that: myframe <- data.frame (ID=c("Ernie", "Ernie", "Ernie", "Bert", "Bert", "Bert"), Timestamp=c("24.09.2012 09:00", "24.09.2012 10:00", "24.09.2012 11:00"), Hunger=c(1,1,1,2,2,1) ) myframestime <- as.POSIXct (strptime(as.character(myframe$Timestamp),

Hi WizaRds, What is the "standard" way to get the day of the week from a date such as as.Date("2006-12-01")? It looks like fCalendar has some functions but this requires a change in the R locale to GMT. Is there another way? Thanks! Jack. --------------------------------- Be a PS3 game guru. [[alternative HTML version deleted]]

Hello everyone, I want to split a data.frame by the column date . The data frame looks like this date time open close 02.01.2011 09:00:00 1000 1200 02.01.2011 09:05:02 1200 1203 ... 01.02.2011 10:01:21 1029 1110 ..... 30.03.2011 12:02:12 1231 1200

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