Rui is right -- lubridate functionality and robustness is better -- but
just for fun, here is a simple function, poorly named reformat(), that
splits up the date formats, cleans them up and standardizes them a bit, and
spits them back out with a sep character of your choice (your original
split and recombine suggestion). Lubridate probably does something similar
but more sophisticated, but maybe it's worthwhile to see how one can do it
using basic functionality. This only requires a few short lines of code.
reformat <- function(z, sep = "-"){
z <- gsub(" ","",z) ## remove blanks
## break up dates into 3 component pieces and convert to matrix
z <- matrix(unlist(strsplit(z, "-|/")), nrow = 3)
## add "0" in front of single digit in dd and mm
## add "20" in front of "yy"
for(i in 1:2) z[i, ] <-
gsub("\\<([[:digit:]])\\>","0\\1",z[i, ])
z[3, ] <-
sub("\\<([[:digit:]]{2})\\>","20\\1",z[3, ])
## combine back into single string separated by sep
paste(z[1, ],z[2, ],z[3, ], sep = sep)
}
## Testit> z <- c(" 1 / 22 /2015"," 1 -5
-15","11/7/2016", "14-07-16")
> reformat(z)
[1] "01-22-2015" "01-05-2015" "11-07-2016"
"14-07-2016"
> reformat(z,"/")
[1] "01/22/2015" "01/05/2015" "11/07/2016"
"14/07/2016"
Bert Gunter
"The trouble with having an open mind is that people keep coming along and
sticking things into it."
-- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
On Sun, Nov 3, 2019 at 12:15 AM Rui Barradas <ruipbarradas at sapo.pt>
wrote:
> Hello,
>
> I believe the simplest is to use package lubridate. Its functions try
> several formats until either one is right or none fits the data.
>
> x <- c('11/7/2016', '14-07-16')
> lubridate::dmy(x)
> #[1] "2016-07-11" "2016-07-14"
>
>
> The order dmy must be the same for all vector elements, if not
>
> y <- c('11/7/2016', '14-07-16', '2016/7/11')
> lubridate::dmy(y)
> #[1] "2016-07-11" "2016-07-14" NA
> #Warning message:
> # 1 failed to parse.
>
>
> Hope this helps,
>
> Rui Barradas
>
> ?s 02:25 de 03/11/19, reichmanj at sbcglobal.net escreveu:
> > R-Help Forum
> >
> >
> >
> > I have a data set that contains a date field but the dates are in two
> > formats
> >
> >
> >
> > 11/7/2016 dd/mm/yyyy
> >
> > 14-07-16 dd-mm-yy
> >
> >
> >
> > How would I go about correcting this problem. Should I separate the
> dates,
> > format them , and then recombine?
> >
> >
> >
> > Sincerely
> >
> >
> >
> > Jeff Reichman
> >
> > (314) 457-1966
> >
> >
> >
> >
> > [[alternative HTML version deleted]]
> >
> > ______________________________________________
> > 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.
> >
>
> ______________________________________________
> 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.
>
[[alternative HTML version deleted]]
On 11/3/19 11:51 AM, Bert Gunter wrote:> Rui is right -- lubridate functionality and robustness is better -- but > just for fun, here is a simple function, poorly named reformat(), that > splits up the date formats, cleans them up and standardizes them a bit, and > spits them back out with a sep character of your choice (your original > split and recombine suggestion). Lubridate probably does something similar > but more sophisticated, but maybe it's worthwhile to see how one can do it > using basic functionality. This only requires a few short lines of code.If one wants to investigate existing efforts at automatic date _and_ time reformatting, then do not forget Dirk's anytime package: https://cran.r-project.org/web/packages/anytime/index.html -- David.> > reformat <- function(z, sep = "-"){ > z <- gsub(" ","",z) ## remove blanks > ## break up dates into 3 component pieces and convert to matrix > z <- matrix(unlist(strsplit(z, "-|/")), nrow = 3) > ## add "0" in front of single digit in dd and mm > ## add "20" in front of "yy" > for(i in 1:2) z[i, ] <- gsub("\\<([[:digit:]])\\>","0\\1",z[i, ]) > z[3, ] <- sub("\\<([[:digit:]]{2})\\>","20\\1",z[3, ]) > ## combine back into single string separated by sep > paste(z[1, ],z[2, ],z[3, ], sep = sep) > } > > ## Testit >> z <- c(" 1 / 22 /2015"," 1 -5 -15","11/7/2016", "14-07-16") >> reformat(z) > [1] "01-22-2015" "01-05-2015" "11-07-2016" "14-07-2016" > >> reformat(z,"/") > [1] "01/22/2015" "01/05/2015" "11/07/2016" "14/07/2016" > > Bert Gunter > > "The trouble with having an open mind is that people keep coming along and > sticking things into it." > -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) > > > On Sun, Nov 3, 2019 at 12:15 AM Rui Barradas <ruipbarradas at sapo.pt> wrote: > >> Hello, >> >> I believe the simplest is to use package lubridate. Its functions try >> several formats until either one is right or none fits the data. >> >> x <- c('11/7/2016', '14-07-16') >> lubridate::dmy(x) >> #[1] "2016-07-11" "2016-07-14" >> >> >> The order dmy must be the same for all vector elements, if not >> >> y <- c('11/7/2016', '14-07-16', '2016/7/11') >> lubridate::dmy(y) >> #[1] "2016-07-11" "2016-07-14" NA >> #Warning message: >> # 1 failed to parse. >> >> >> Hope this helps, >> >> Rui Barradas >> >> ?s 02:25 de 03/11/19, reichmanj at sbcglobal.net escreveu: >>> R-Help Forum >>> >>> >>> >>> I have a data set that contains a date field but the dates are in two >>> formats >>> >>> >>> >>> 11/7/2016 dd/mm/yyyy >>> >>> 14-07-16 dd-mm-yy >>> >>> >>> >>> How would I go about correcting this problem. Should I separate the >> dates, >>> format them , and then recombine? >>> >>> >>> >>> Sincerely >>> >>> >>> >>> Jeff Reichman >>> >>> (314) 457-1966 >>> >>> >>> >>> >>> [[alternative HTML version deleted]] >>> >>> ______________________________________________ >>> 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. >>> >> ______________________________________________ >> 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. >> > [[alternative HTML version deleted]] > > ______________________________________________ > 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.
Yes, indeed. Thanks, David. Cheers, Bert On Sun, Nov 3, 2019 at 12:22 PM David Winsemius <dwinsemius at comcast.net> wrote:> > On 11/3/19 11:51 AM, Bert Gunter wrote: > > Rui is right -- lubridate functionality and robustness is better -- but > > just for fun, here is a simple function, poorly named reformat(), that > > splits up the date formats, cleans them up and standardizes them a bit, > and > > spits them back out with a sep character of your choice (your original > > split and recombine suggestion). Lubridate probably does something > similar > > but more sophisticated, but maybe it's worthwhile to see how one can do > it > > using basic functionality. This only requires a few short lines of code. > > If one wants to investigate existing efforts at automatic date _and_ > time reformatting, then do not forget Dirk's anytime package: > > > https://cran.r-project.org/web/packages/anytime/index.html > > > -- > > David. > > > > > reformat <- function(z, sep = "-"){ > > z <- gsub(" ","",z) ## remove blanks > > ## break up dates into 3 component pieces and convert to matrix > > z <- matrix(unlist(strsplit(z, "-|/")), nrow = 3) > > ## add "0" in front of single digit in dd and mm > > ## add "20" in front of "yy" > > for(i in 1:2) z[i, ] <- gsub("\\<([[:digit:]])\\>","0\\1",z[i, ]) > > z[3, ] <- sub("\\<([[:digit:]]{2})\\>","20\\1",z[3, ]) > > ## combine back into single string separated by sep > > paste(z[1, ],z[2, ],z[3, ], sep = sep) > > } > > > > ## Testit > >> z <- c(" 1 / 22 /2015"," 1 -5 -15","11/7/2016", "14-07-16") > >> reformat(z) > > [1] "01-22-2015" "01-05-2015" "11-07-2016" "14-07-2016" > > > >> reformat(z,"/") > > [1] "01/22/2015" "01/05/2015" "11/07/2016" "14/07/2016" > > > > Bert Gunter > > > > "The trouble with having an open mind is that people keep coming along > and > > sticking things into it." > > -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) > > > > > > On Sun, Nov 3, 2019 at 12:15 AM Rui Barradas <ruipbarradas at sapo.pt> > wrote: > > > >> Hello, > >> > >> I believe the simplest is to use package lubridate. Its functions try > >> several formats until either one is right or none fits the data. > >> > >> x <- c('11/7/2016', '14-07-16') > >> lubridate::dmy(x) > >> #[1] "2016-07-11" "2016-07-14" > >> > >> > >> The order dmy must be the same for all vector elements, if not > >> > >> y <- c('11/7/2016', '14-07-16', '2016/7/11') > >> lubridate::dmy(y) > >> #[1] "2016-07-11" "2016-07-14" NA > >> #Warning message: > >> # 1 failed to parse. > >> > >> > >> Hope this helps, > >> > >> Rui Barradas > >> > >> ?s 02:25 de 03/11/19, reichmanj at sbcglobal.net escreveu: > >>> R-Help Forum > >>> > >>> > >>> > >>> I have a data set that contains a date field but the dates are in two > >>> formats > >>> > >>> > >>> > >>> 11/7/2016 dd/mm/yyyy > >>> > >>> 14-07-16 dd-mm-yy > >>> > >>> > >>> > >>> How would I go about correcting this problem. Should I separate the > >> dates, > >>> format them , and then recombine? > >>> > >>> > >>> > >>> Sincerely > >>> > >>> > >>> > >>> Jeff Reichman > >>> > >>> (314) 457-1966 > >>> > >>> > >>> > >>> > >>> [[alternative HTML version deleted]] > >>> > >>> ______________________________________________ > >>> 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. > >>> > >> ______________________________________________ > >> 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. > >> > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > 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. >[[alternative HTML version deleted]]
> On 3 Nov 2019, at 21:22 , David Winsemius <dwinsemius at comcast.net> wrote: > > > On 11/3/19 11:51 AM, Bert Gunter wrote:====== Hey, that's my birthday! Err, no it isn't... ;-) -- Peter Dalgaard, Professor, Center for Statistics, Copenhagen Business School Solbjerg Plads 3, 2000 Frederiksberg, Denmark Phone: (+45)38153501 Office: A 4.23 Email: pd.mes at cbs.dk Priv: PDalgd at gmail.com