[R] reading dates in Excel into R

[Gray Calhoun]

Hi Hongying,
  There is a manual on the R website about data import and export that
explains different options.
--Gray

On 7/30/10, Hongying Li <colorleaf at hotmail.com> wrote:
>
>  I just do not want the dates format change randomly (seems to me) each time
> I read it from excel2007 file into R.
> When I export the excel2007 fiel into csv file and use read.csv function
> then the dates all come out good (as mm/dd/yyyy in csv file).
> I guess I have to first import into csv file before reading into R. Just
> avoid reading from Excel2007 files directly.
> Thanks,
> Hongying
>
>
>
>> Date: Fri, 30 Jul 2010 10:24:50 +0100
>> Subject: Re: [R] reading dates in Excel into R
>> From: frainj at gmail.com
>> To: Peter.Alspach at plantandfood.co.nz
>> CC: colorleaf at hotmail.com; r-help at r-project.org
>>
>> To read the data into R
>> 1) I format my dates as YYYY-MM-DD in Excel (or OpenOffice Calc),
>> 2) (change =na() to NA)
>> 3) Check that required number of significant decimal places are displayed,
>> 4) export as csv and
>> 5) Use readSeries() function from Rmetrics timeSeries package to read
>> the data into R.
>>
>> For what it is worth I have found this approach flexible .
>>
>> Best Regards
>>
>> John
>>
>> On 29 July 2010 22:18, Peter Alspach <Peter.Alspach at plantandfood.co.nz>
>> wrote:
>> > Tena koe
>> >
>> > What do you want to control?  You can govern the format used in R using
>> > the appropriate R functions.  I doubt it would be useful to have dates
>> > read from Excel depend on the format set for displaying those dates in
>> > Excel.
>> >
>> > HTH ....
>> >,,,
>>
>> > Peter Alspach
>> >
>> >> -----Original Message-----
>> >> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
>> >> project.org] On Behalf Of Hongying Li
>> >> Sent: Friday, 30 July 2010 5:33 a.m.
>> >> To: r-help at r-project.org
>> >> Subject: [R] reading dates in Excel into R
>> >>
>> >>
>> >> I am reading dates in Excel2007 into R.
>> >>
>> >> Here are the functions I used:
>> >>
>> >> library(RODBC)
>> >> channel<-odbcConnectExcel2007("myfile.xlsx")
>> >> tmp<-sqlFetch(channel,"1",as.is=T)
>> >>
>> >>
>> >> The dates in myfile.xlsx are all in this format: mm/dd/yyyy. But when I
>> >> read it to R, some columns look like "yyyy-mm-dd 00:00:00", some
>> >> columns look like "yyyy-mm-dd", and some columns are numbers. I do not
>> >> know how I can control this.
>> >>
>> >>
>> >>
>> >> Any help? Thanks!
>> >>
>> >>
>> >>
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>> >> ______________________________________________
>> >> 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.
>> >
>> > ______________________________________________
>> > 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.
>> >
>>
>>
>>
>> --
>> John C Frain
>> Economics Department
>> Trinity College Dublin
>> Dublin 2
>> Ireland
>> www.tcd.ie/Economics/staff/frainj/home.html
>> mailto:frainj at tcd.ie
>> mailto:frainj at gmail.com
>  		 	   		
> 	[[alternative HTML version deleted]]
>
> ______________________________________________
> 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.
>


-- 
Gray Calhoun

Assistant Professor of Economics, Iowa State University
http://www.econ.iastate.edu/~gcalhoun/