similar to: Subject: RE: Time plot question.

The following is an example of a dataframe containing times, plus some numeric data. foo <- c("12:39:26","12:40:22","12:41:19") bar <- data.frame(foo,1:3,11:13) Note that the times are of class 'factor' (their class changes in this case, as they go into the dataframe). To convert this dataframe to an 'its', do the following: library(its)

Dear list: working with date/times I have come across a problem that ISOdate and ISOdatetime are too slow on large vectors of data. I was surprised just until I looked at the implementation and the man page: "ISOdatetime and ISOdate are convenience wrappers for strptime". In other terms, they convert data to character representation first in order to create a POSIXlt object that is then

I have asked this question before, and received some suggestions for work-arounds that get the job done--and they are much appreciated. But I would still like to find out if I'm missing something, and whether there is a direct way using POSIXt functions (as.POSIXct, as.POSIXlt, strptime, in particular). I have environmental data collected once per minute. Here is a subset of 3 input

hi again I will try this time to explain my problem clearly I have the following data from the file skiing.csv (3 first rows) protokollid date start end 1 4 2/23/2009 8:50:10 15:17:30 2 4 2/24/2009 9:47:00 13:52:25 3 5 3/22/2009 8:51:25 12:00:05 I have the following script library(chron) skiers=read.csv("skiing.csv")

In the base package, as.POSIXct() is an S3 generic function, but as.POSIXlt() is not. As shown below, the current implementation is already crying out to be refactored into a generic function with methods for various classes. It calls "inherits" five times. Not only is this bad style, it also disallows me or anyone else from making as.POSIXlt() work with other kinds of time-ish

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

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

Hi all, I have multiple datasets of time series data taken from GPS collars. The collars are supposed to take a fix every hour on the half hour, i.e., 0:30, 1:30, 2:30...23:30, (because it sometimes takes longer for the collars to acquire a location the minute of these locations vary from 30-34) but because of a software glitch in the collars, at random times the collars start taking multiple

R-devel: Some very inconsistent behavior, that I can't seem to find documented. Sys.setenv(TZ="GMT") str(unclass(strptime("1969-12-31 23:59:59","%Y-%m-%d %H:%M:%S"))) List of 9 $ sec : num 59 $ min : int 59 $ hour : int 23 $ mday : int 31 $ mon : int 11 $ year : int 69 $ wday : int 3 $ yday : int 364 $ isdst: int 0 - attr(*, "tzone")= chr

When I try to do linear interpolation between financial contracts with maturities on different dates in different months I have come across some behavior I haven't seen before. I have a data frame in R which is loaded from an access database so I can't provide a working example. It was loaded using this code: > dbPath <- "H:/pathToDB/DB.mdb" > channel <-

[I am herewith re-posting this message on R-devel, as it seems to be the most appropriate mailing list for this issue.] Dear List, >From what I understand, strptime() simply converts from one class representation to another; i.e., from character to POSIXct/POSIXlt. One strange feature of this command running on Linux is that there are repeated calls to system time (as was revealed

Hello all, I am having a little trouble working with "strptime" and I was hoping someone might be able to give me a hand. I have an instrument that outputs an ordinal date and time in two columns something like this: day.hour min.sec 1 12525 2050 2 12518 2029 3 12524 2023 4 12524 2028 5 12507 2035 Now the problem I am having is converting these numbers

Hi, I am computing some time differences. Using the linux version of R 2.7.1 And I am getting a strange result ( see below ) I need the difference in minutes. Actually looking for where it is NOT 15 minutes. Would anyone know why this could be happening? Or should I do this another way? Bill The script "k0.R" =============== a=read.table("buzwah005.txt")

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

Dear List, For what I understand, strptime() simply converts from one class representation to another; i.e., from character to POSIXct/POSIXlt. One strange feature of this command running on Linux is that there are repeated calls to system time (as was revealed in a trace of system calls), which considerably affect performance. These system calls end up taking almost 75% of the execution

Hi, You don't give the time zone but this is probably due to the clock jumping by one hour when switching to summer time. In UK this happens at 1am and on that day there is no such thing as 01:05, etc., see eg https://www.timeanddate.com/time/change/uk/london In your time zone this probably happens at 2am. Georgi Boshnakov ------------------------------ Message: 7 Date: Thu, 26 Jan 2017

Hello, Im reading Data out of a Database. #v+ rs <- dbGetQuery(con,"SELECT * ... ) attach(rs) #v- There ist a colum I convert into "Time". #v+ > zeit<-strptime(datum,format="%Y-%m-%d %H:%M:%S"); > class(zeit) [1] "POSIXt" "POSIXlt" #v- 1. A plot(zeit,money) plots the Data. All i see on the x-achis are the Days. I would like to see the

I've been trying to build R 3.3.1 inside of a Nix environment on a Ubuntu 16.04 machine. It builds, but then it fails a regression test related to time zones, and I hope that someone could help me debug the problem. The failing test is in tests/reg-tests-rc.R (https://github.com/wch/r-source/blob/c3fe9cd4/tests/reg-tests-1c.R#L1577-L1587): ## format.POSIXlt() of Jan.1 if 1941 or '42 is

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

Hi Herry, This is probably due to a call to strptime (or similar). No, it doesn't accept %Y-%m as a valid format. Maybe add a constant day to all the dates as that will work: dt<-list(ID=seq(1:24),month=rep(formatC(1:12,flag=0,width=2),2), year=sort(rep(2016:2017,12))) timelst<-paste(unlist(dt['year']),unlist(dt['month']),"01",sep="-")