[R] Alternative to extended recode sintax? Bug?

[Luca Meyer]

Yes, I am seeing that at the end of 2010-beginning 2011. Try:

weekdays(as.POSIXct("2010-12-25")+(0:20)*24*60*60)
week(as.POSIXct("2010-12-25")+(0:20)*24*60*60)

Week 1 (2011) is made up of 6 days....

Luca

Il giorno 20/dic/2010, alle ore 17.54, David Winsemius ha scritto:

> 
> On Dec 20, 2010, at 10:58 AM, Luca Meyer wrote:
> 
>> Right, I appreciate the first day of the year start date. I am just wondering why then the cut off day is not the same for the rest of the year...but it's all right to use other packages.
> 
> Are you saying it shifts within the year? I am not seeing that:
> 
> require(lubridate)
> 
> > weekdays(as.POSIXct("2010-01-01")+(0:8)*24*60*60)
> [1] "Friday"    "Saturday"  "Sunday"    "Monday"    "Tuesday"   "Wednesday"
> [7] "Thursday"  "Friday"    "Saturday"
> > week(as.POSIXct("2010-01-01")+(0:8)*24*60*60)
> [1] 1 1 1 1 1 1 2 2 2
> 
> Looks to be incrementing weeks between Wed and Thurs at the beginning of the year just as it did in your example. I admit that I thought that it should be shifting at the Thursday - Friday divide, but setting a zero point can be ambiguous. I thought if it were  Midnight Thursday-Friday that all of Thurdays would be in week 1. But at least it appears consistent.
> 
> 
>> Thanks,
>> Luca
>> 
>> Il giorno 20/dic/2010, alle ore 14.16, David Winsemius ha scritto:
>> 
>>> 
>>> On Dec 20, 2010, at 12:54 AM, Luca Meyer wrote:
>>> 
>>>> All right, I get it now: lubridate's week() define weeks from Thursday till the following Wednesday. You'd probably agree with me that it's a bit strange what it is going to do over the turn of the year:
>>>> 
>>>>> y <- as.POSIXct(c("2010-12-27","2010-12-28","2010-12-29","2010-12-30","2010-12-31","2011-01-01","2011-01-02","2011-01-03","2011-01-04","2011-01-05","2011-01-06","2011-01-07","2011-01-08","2011-01-09","2011-01-10","2011-01-11","2010-01-12","2010-01-13","2010-01-14"))
>>>>> week(y)
>>>> [1] 52 52 52 53 53  1  1  1  1  1  1  2  2  2  2  2  2  2  3
>>>> 
>>>> Why would the first week of the year be made of 6 days and the turn from week 1 to week 2 on the night between Thursday and Friday and not Wednesday and Friday like every other week?
>>> 
>>> weeks in lubridate start on whatever day of the week is the first of that year.
>>> 
>>> If you want a Monday starting day (or the option to change to another starting day), then package chron has such facilities.
>>> 
>>> 
>>>> 
>>>> Cheers,
>>>> Luca
>>>> 
>>>> 
>>>> 
>>>> Il giorno 19/dic/2010, alle ore 18.14, Uwe Ligges ha scritto:
>>>> 
>>>>> 
>>>>> 
>>>>> On 19.12.2010 13:20, David Winsemius wrote:
>>>>>> 
>>>>>> On Dec 19, 2010, at 5:11 AM, Luca Meyer wrote:
>>>>>> 
>>>>>>> Something goes wrong with the week function of the lubridate package:
>>>>>>> 
>>>>>>>> x= as.POSIXct(factor(c("2010-12-15 17:28:27",
>>>>>>> + "2010-12-15 17:32:34",
>>>>>>> + "2010-12-15 18:48:39",
>>>>>>> + "2010-12-15 19:25:00",
>>>>>>> + "2010-12-16 08:00:00",
>>>>>>> + "2010-12-16 08:25:49",
>>>>>>> + "2010-12-16 09:00:00")))
>>>>>>>> require(lubridate)
>>>>>> 
>>>>>>>> weekdays(x)
>>>>>>> [1] "Mercoledì" "Mercoledì" "Mercoledì" "Mercoledì" "Giovedì"
>>>>>>> "Giovedì" "Giovedì"
>>>>>>>> week(x)
>>>>>>> [1] 50 50 50 50 51 51 51
>>>>>> 
>>>>>> But 2010-12-15 is a Wednesday and 2010-12-16 is a Thursday.
>>>>>> 
>>>>> 
>>>>> 
>>>>> Together with the description of ?week this shows that lubridate's week() function works as documented rather than as expected by Luca Meyer.
>>>>> 
>>>>> Uwe Ligges
>>>> 
>>> 
>>> David Winsemius, MD
>>> West Hartford, CT
>>> 
>> 
> 
> David Winsemius, MD
> West Hartford, CT
>