re placing the dates format in R for exporting the data set...
On Nov 18, 2009, at 11:00 PM, ychu066 wrote:
hey Jim , I have solve the column name problems now. But i am still unable to read the date in R ... toms_dat<- replace(toms_dat, toms_dat ==2009-08-24, 6)
replace needs its first argument to be a vector, while you have given
it a dataframe.
Look at these examples:
> toms <- data.frame(a=letters[1:10], b=Sys.Date() + 1:10)
> toms
a b
1 a 2009-11-20
2 b 2009-11-21
3 c 2009-11-22
4 d 2009-11-23
5 e 2009-11-24
6 f 2009-11-25
7 g 2009-11-26
8 h 2009-11-27
9 i 2009-11-28
10 j 2009-11-29
> replace(toms$b, toms$b=="2009-11-23", 6)
Error in as.Date.numeric(value) : 'origin' must be supplied
Notice that this did not
> replace(toms$b, toms$b=="2009-11-23", "2008-01-01")
[1] "2009-11-20" "2009-11-21" "2009-11-22" "2008-01-01" "2009-11-24"
"2009-11-25" "2009-11-26"
[8] "2009-11-27" "2009-11-28" "2009-11-29"
> toms
a b
1 a 2009-11-20
2 b 2009-11-21
3 c 2009-11-22
4 d 2009-11-23
5 e 2009-11-24
6 f 2009-11-25
7 g 2009-11-26
8 h 2009-11-27
9 i 2009-11-28
10 j 2009-11-29
Notice that the replace() operation did not do anything to "toms". If
you had wanted it to, you would have needed to do:
toms$b <- replace(toms$b, toms$b=="2009-11-23", "2008-01-01")
Now, if you want further assistance you need to provide a working
excaple that has the same features as your problem. Use str(toms_dat)
to see what type your columns are ant then perhaps:
dput(head(toms_dat))
or:
dump("toms_dat", file=stdout() )
or if toms_dat is big, then:
smalltoms <- head(toms_dat)
dump("smalltoms", stdout() )
the toms_dat is a data frame , and I want to replace the date to be a single number eg:1,2,3, .... regards, Tom. jholtman wrote:
First of all '2009-08-06' is 1995; this is probably not what you were expecting. What do you what your expression to do? Is 'toms_dat' a dataframe? if so, your expression 'toms_dat ==2009-08-06' seem strange. So tell us what you want to do, not how you want to do it. On Tue, Nov 17, 2009 at 4:54 PM, ychu066 <ychu066 at aucklanduni.ac.nz> wrote:
hi everyone, i am having difficulties with replacing the dates format in R for exporting the data set... eg: the code that i used was toms_dat<- replace(toms_dat, toms_dat ==2009-08-06, 2) toms_dat<- replace(toms_dat, toms_dat ==2009-08-04, 1) but when i export the data as into txt file or excel file the dates come up with very large numbers .....:drunk: please help me ...=) -- View this message in context: http://old.nabble.com/replacing-the-dates-format-in-R-for-exporting-the-data-set...-tp26396492p26396492.html Sent from the R help mailing list archive at Nabble.com.
______________________________________________ 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.
-- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve?
______________________________________________ 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.
-- View this message in context: http://old.nabble.com/replacing-the-dates-format-in-R-for-exporting-the-data-set...-tp26396492p26420068.html Sent from the R help mailing list archive at Nabble.com.
______________________________________________ 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.
David Winsemius, MD Heritage Laboratories West Hartford, CT