similar to: difftime arithmetic (PR#2345)

Since both comparison and negation are well-defined for time differences, I wonder why abs and division are not defined for class difftime. This behavior is clearly documented on the man page: "limited arithmetic is available on 'difftime' objects"; but why? Both are natural, semantically sound, and useful operations and I see no obvious reason that they should give an error:

Since both comparison and negation are well-defined for time differences, I wonder why abs and division are not defined for class difftime. This behavior is clearly documented on the man page: "limited arithmetic is available on 'difftime' objects"; but why? Both are natural, semantically sound, and useful operations and I see no obvious reason that they should give an error:

Full_Name: Suharto Anggono Version: 2.8.1 OS: Windows Submission from: (NULL) (125.165.81.48) There is already PR#13369. But, the problem is not just the warning. C:\Program Files\R\R-2.8.1\bin>R --vanilla R version 2.8.1 (2008-12-22) Copyright (C) 2008 The R Foundation for Statistical Computing ISBN 3-900051-07-0 R is free software and comes with ABSOLUTELY NO WARRANTY. You are welcome

Anybody have an idea why I would get a non-integer value for the number of days here? > difftime('2004-08-05','2001-01-03',units='days') Time difference of 1309.958 days Would you just round off? Best, Jon

I've just spent today trying to fix a Heisenbug... this function returns a linear interpolator function: interpOne <- function(xl,yl){ f = function(data){ t = (data-min(xl))/(max(xl)-min(xl)) return(min(yl)+t*(max(yl)-min(yl))) } return(f) } > k=interpOne(c(0,1),c(4,5)) > k(0.5) [1] 4.5 and this function uses the above to return a function that returns a piece-wise

Full_Name: Hong Ooi Version: 2.10.0 OS: Windows XP Submission from: (NULL) (203.110.235.1) While trying to get summary statistics on a duration variable (the difference between a start and end date), I ran into the following issue. Using summary or quantile (which summary calls) on a difftime object takes an extremely long time if the object is even moderately large. A reproducible example:

If you apply the "max" function to a vector of class "difftime" with units="days", the returned value is in units of "seconds". Is this not a bug? At any rate it can lead to confusing results if one buries a call to "max" deep in some data analysis code. Details: > y<-structure(1, class = "difftime", units = "days")

On Thu, Jun 10, 2010 at 3:39 PM, Gustaf Rydevik <gustaf.rydevik at gmail.com> wrote: > Hi all, > > The recent change in 2.11 that made as.numeric() return false on > difftime-objects broke some of my code that calculated age classes of > individuals using cut(). While this was no big thing to fix for me, it > might be wise > to provide a cut.difftime method to ?stop

On Thu, Jun 10, 2010 at 3:39 PM, Gustaf Rydevik <gustaf.rydevik at gmail.com> wrote: > Hi all, > > The recent change in 2.11 that made as.numeric() return false on > difftime-objects broke some of my code that calculated age classes of > individuals using cut(). While this was no big thing to fix for me, it > might be wise > to provide a cut.difftime method to ?stop

Hello! you, Emil Bode <emil.bode at dans.knaw.nl>, wrote on Tuesday, July 31, 2018 1:55 PM: > Some of the changes you're proposing could be made (with effort), but note that you're not > restricted to providing strings with a format. > What you're trying to do can be accomplished with as.difftime(12, units='weeks'), see also > ?as.difftime > > Or if

I am trying to write S4 methods with "difftime" in the signature but am being "informed" (? not a warning or error) that "difftime" is not a class. Nevertheless, dispatch takes place. Should I simply ignore that "information"? Here is a toy example: > setClass("foo", contains = "Date") > setMethod("+", c("foo",

R-listers, I have noticed several posts on issues with difftime producing NA's but they have been for older versions of R. Here's the issue associated with difftime that I am dealing with in R 2.12.2. > preciptime = strptime("01/10/2007 14:00",format="%m/%d/%Y %H:%M") > class(preciptime) [1] "POSIXlt" "POSIXt" > # Now using difftime, this

I'm new to R and have the following problem with difftime: if I directly assign date/time strings in difftime I get the expected result: > a<-"2010-03-23 10:52:00" > a [1] "2010-03-23 10:52:00" > b<-"2010-03-23 11:53:00" > u2<-as.difftime(c(a,b), format ="%Y-%m-%d %H:%M:%S", units="mins") > u2 Time differences in mins

It seems that there are several folks Out There with an itch to scratch with respect to difftimes. http://article.gmane.org/gmane.comp.lang.r.devel/19223/match=difftime http://article.gmane.org/gmane.comp.lang.r.devel/18441/match=difftime http://article.gmane.org/gmane.comp.lang.r.devel/10882/match=difftime http://article.gmane.org/gmane.comp.lang.r.devel/11675/match=difftime and I might be

Hi, I am trying to take difference of two time objects. I want to fix the result's unit to minutes. How can I do that? Here is an example: > difftime(x, y) Time difference of 2.030720 hours > difftime(x, z) Time difference of 30.34672 mins where x = '2007-03-05 08:32:58' y = '2007-03-05 06:31:07' and z = '2007-03-05 08:02:37' How can I get answer

Hello, ?DateTimeClasses states that "one can add or subtract a number of seconds or a 'difftime' object from a date-time object, but not add two date-time objects." So, is the below expected behavior? > x <- Sys.time() > x [1] "2007-02-21 16:19:56 CST" > x + as.difftime("1","%H") [1] "2007-02-21 16:19:57 CST" Warning

Dear all, according to the Help-page of DateTimeClasses {base} I should be able to do time - z with time date-time objects z a numeric vector (in seconds) or an object of class "difftime". However, on R version 2.6.0 (Windows XP) I get > Sys.time() - as.difftime(c("0:3:20", "11:23:15")) Time differences in mins [1] 1191837998 1191837318

Dear all, I have a vector generated using the function strptime: > my.dt [1] "2004-04-19 08:35:00 W. Europe Daylight Time" "2004-04-19 09:35:00 W. Europe Daylight Time" "2004-04-19 11:35:00 W. Europe Daylight Time" [4] "2004-04-19 13:35:00 W. Europe Daylight Time" "2004-04-20 07:50:00 W. Europe Daylight Time" > class(my.dt) [1]

Dear list, "+" (and "-") being defined for difftime class, I expected mean() to return something sensible. This is only half-true : > mean(c(1:5, 5:1),na.rm=TRUE) [1] 3 > mean(as.difftime(c(1:5, 5:1),unit="mins"),na.rm=TRUE) Time difference of 3 mins Fine so far. However : > mean(c(1:5, NA,5:1),na.rm=TRUE) [1] 3 > mean(as.difftime(c(1:5,

I just encountered another RTFM problem: With diff(as.POSIXct(...), ...) I was unable to control the units of the results. Examples: > (d.d <- diff(as.POSIXct(c('2012-12-12', '2012-12-13')))) Time difference of 1 days > (d.h <- diff(as.POSIXct(c('2012-12-12 08:00', '2012-12-12 09:00')))) Time difference of 1 hours > (d.m <-