[R] Date extract Year

[Spencer Graves]

       The Ecfun package includes a function "as.Date1970", that merely 
provides a default origin for "as.Date".


       This kind of thing can be found using


library(sos)
findFn('as.Date1970')


       This produced a list in my default browser showing 4 links in 3 
packages, the first 2 of which were for this.


       Hope this helps.
       Spencer


On 3/8/2015 9:51 AM, Bert Gunter wrote:
> Please read ?as.Date carefully. Your argument appears to be numeric
> (??)  and you do not seem to have specified an origin:
>
> "as.Date will accept numeric data (the number of days since an epoch),
> but only if origin is supplied."
>
> Cheers,
> Bert
>
> Bert Gunter
> Genentech Nonclinical Biostatistics
> (650) 467-7374
>
> "Data is not information. Information is not knowledge. And knowledge
> is certainly not wisdom."
> Clifford Stoll
>
>
>
>
> On Sat, Mar 7, 2015 at 5:49 PM, Steve Archambault <archstevej at gmail.com> wrote:
>> Hi all,
>>
>> I am trying in vain to create a new object "Year" in my data frame from
>> existing Date data. I have tried many different approaches, but can't seem
>> to get it to work. Here is an example of some code I tried.
>>
>> date1<- as.Date(wells$Date,"%m/%d/%Y")
>> wells$year<-as.numeric(format(date1, "%Y"))
>>
>> I am starting with data that looks like this.
>>
>>          ID  Date DepthtoWater_bgs test test2
>> 1  BC-0004 41163           260.60    3     1
>> 2  BC-0004 41255           261.65    4     2
>> 3  BC-0003 41345           166.58    5     3
>> 4  BC-0002 41351           317.85    6     4
>> 5  BC-0004 41355           262.15    7     5
>> 6  BC-0003 41438           167.55    8     6
>> 7  BC-0004 41438           265.45    9     7
>> 8  BC-0002 41443           317.25   10     8
>> 9  BC-0002 41521           321.25   11     9
>> 10 BC-0003 41522           168.65   12    10
>> 11 BC-0004 41522           266.15   13    11
>> 12 BC-0003 41627           168.95   14    12
>> 13 BC-0004 41627           265.25   15    13
>> 14 BC-0002 41634           312.31   16    14
>> 15 BC-0003 41703           169.25   17    15
>> 16 BC-0004 41703           265.05   18    16
>> 17 BC-0002 41710           313.01   19    17
>> 18 BC-0003 41795           168.85   20    18
>> 19 BC-0004 41795           266.95   21    19
>> 20 BC-0002 41801           330.41   22    20
>> 21 BC-0003 41905           169.75   23    21
>> 22 BC-0004 41905           267.75   24    22
>> 23 BC-0002 41906           321.01   25    23
>>
>> Any help would be greatly appreciated!
>>
>>
>> -Steve
>>
>> ______________________________________________
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>> and provide commented, minimal, self-contained, reproducible code.
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.