[R] Looking for a special date function in R

[Sergey Goriatchev]

Thank you all for your help!

Sergey

On Wed, Jan 21, 2009 at 13:25, Gabor Grothendieck
<ggrothendieck at gmail.com> wrote:
> This will give you 6 months after today.  Use negative
> numbers to move backwards:
>
>> d <- Sys.Date()
>> seq(d, length = 2, by = paste(6, "months"))[2]
> [1] "2009-07-21"
>
>
> On Wed, Jan 21, 2009 at 6:27 AM, Sergey Goriatchev <sergeyg at gmail.com> wrote:
>> Dear Gabor,
>>
>> Thanks for that!
>> Still, it is not really similar to how EDATE works.
>> With julian(Sys.Date(), Sys.Date() - 10)  one moves 10 days back.
>> The problem is that I need to move by months, not by days, as months
>> have different number of days.
>> I need to come to the same day when I move backward or forward in
>> time, for example going back one month from today (21.01.2009) I need
>> to come to 21.12.2008.
>> I've read through your article in RNews 4/1 but still do not know how
>> to do what I need to do.
>>
>> Regards,
>> Sergey
>>
>> On Wed, Jan 21, 2009 at 10:44, Gabor Grothendieck
>> <ggrothendieck at gmail.com> wrote:
>>> See ?julian
>>>
>>>> julian(Sys.Date(), Sys.Date() - 10) # 10
>>> [1] 10
>>> attr(,"origin")
>>> [1] "2009-01-11"
>>>
>>> and R News 4/1.
>>>
>>> On Wed, Jan 21, 2009 at 4:37 AM, Sergey Goriatchev <sergeyg at gmail.com> wrote:
>>>> Hello, everyone
>>>>
>>>> I wonder if R has something similar to Excel function
>>>> EDATE(start_date; months) which returns a serial number of the date
>>>> that is the indicated number of months before of after the start date.
>>>> Example (the second column EDATE(first_column; -6)):
>>>> 01.01.1999      01.07.1998
>>>> 02.02.1999      02.08.1998
>>>> 06.03.1999      06.09.1998
>>>>
>>>> I am working with a zoo object where the row names are dates and for
>>>> particular rows I need to find values that were recorded 6 months
>>>> before (or return NA if the date is before the timeseries start).
>>>>
>>>> Maybe someone knows a passable R function for that kind of operation?
>>>>
>>>> Thanks in advance for help!
>>>>
>>>> Best,
>>>> Sergey
>>>>
>>>> ______________________________________________
>>>> R-help at r-project.org mailing list
>>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>>>> and provide commented, minimal, self-contained, reproducible code.
>>>>
>>>
>>
>>
>>
>> --
>> I'm not young enough to know everything. /Oscar Wilde
>> Experience is one thing you can't get for nothing. /Oscar Wilde
>> When you are finished changing, you're finished. /Benjamin Franklin
>> Tell me and I forget, teach me and I remember, involve me and I learn.
>> /Benjamin Franklin
>> Luck is where preparation meets opportunity. /George Patten
>>
>



-- 
I'm not young enough to know everything. /Oscar Wilde
Experience is one thing you can't get for nothing. /Oscar Wilde
When you are finished changing, you're finished. /Benjamin Franklin
Tell me and I forget, teach me and I remember, involve me and I learn.
/Benjamin Franklin
Luck is where preparation meets opportunity. /George Patten