Re: [R] Replace / with - in date
Why don't you try something like : Xd$x=as.date(xd$x,format=%y/%m/%d). -Original Message- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- project.org] On Behalf Of Christian Raschke Sent: Thursday, April 15, 2010 8:28 PM To: r-help@r-project.org Subject: Re: [R] Replace / with - in date Is there anything that speaks against just applying gsub to the factor levels if one would like to keep everything as factors (and not consider true Date classes or character vectors)? I.e: x - c(2000/01/01, 2001/02/01) xd - as.data.frame(x) levels(xd$x) - gsub(/, -, levels(xd$x)) Christian On 04/15/2010 01:08 PM, David Winsemius wrote: On Apr 15, 2010, at 1:51 PM, prem_R wrote: Hi,every one .I have searched the solutions in the forum for replacing my date value which is in a data frame ,01/01/2000 to 01-01-2000 using replace function but got the following warning message x-2000/01/01 xd-as.data.frame(x) xd$x-replace(xd$x,xd$x==/,-) The replace function does not work with factors, it works with (complete) vectors, not substrings. It's also a real hassle to do such operations on factors, so just use character vectors and try gsub instead: x-2000/01/01 xd-as.data.frame(x, stringsAsFactors=FALSE) xd$x2-gsub(/,-, xd$x) xd x x2 1 2000/01/01 2000-01-01 Warning message: In `[-.factor`(`*tmp*`, list, value = -) : invalid factor level, NAs generated Is there any other method of doing it? or am i missing something?. please let me know if you need any more information. Thanks. Prem -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1911391.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. -- Christian Raschke Department of Economics and ISDS Research Lab (HSRG) Louisiana State University Patrick Taylor Hall, Rm 2128 Baton Rouge, LA 70803 cras...@lsu.edu __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting- guide.html and provide commented, minimal, self-contained, reproducible code. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
[R] Replace / with - in date
Hi,every one .I have searched the solutions in the forum for replacing my date value which is in a data frame ,01/01/2000 to 01-01-2000 using replace function but got the following warning message x-2000/01/01 xd-as.data.frame(x) xd$x-replace(xd$x,xd$x==/,-) Warning message: In `[-.factor`(`*tmp*`, list, value = -) : invalid factor level, NAs generated Is there any other method of doing it? or am i missing something?. please let me know if you need any more information. Thanks. Prem -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1911391.html Sent from the R help mailing list archive at Nabble.com. __ R-help@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.
Re: [R] Replace / with - in date
On Apr 15, 2010, at 1:51 PM, prem_R wrote: Hi,every one .I have searched the solutions in the forum for replacing my date value which is in a data frame ,01/01/2000 to 01-01-2000 using replace function but got the following warning message x-2000/01/01 xd-as.data.frame(x) xd$x-replace(xd$x,xd$x==/,-) The replace function does not work with factors, it works with (complete) vectors, not substrings. It's also a real hassle to do such operations on factors, so just use character vectors and try gsub instead: x-2000/01/01 xd-as.data.frame(x, stringsAsFactors=FALSE) xd$x2-gsub(/,-, xd$x) xd x x2 1 2000/01/01 2000-01-01 Warning message: In `[-.factor`(`*tmp*`, list, value = -) : invalid factor level, NAs generated Is there any other method of doing it? or am i missing something?. please let me know if you need any more information. Thanks. Prem -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1911391.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
Thanks Mr.Winsemius for the proposed solution ,it worked fine.But when came to the entire data frame containing 40 rows ,i used the following code as proposed by you a$date1-gsub(/,-,a$date) got the following error: Error in `$-.data.frame`(`*tmp*`, date1, value = character(0)) : replacement has 0 rows, data has 441906 Please provide solution with the problem. Thanks. -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1914541.html Sent from the R help mailing list archive at Nabble.com. __ R-help@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.
Re: [R] Replace / with - in date
Is there anything that speaks against just applying gsub to the factor levels if one would like to keep everything as factors (and not consider true Date classes or character vectors)? I.e: x - c(2000/01/01, 2001/02/01) xd - as.data.frame(x) levels(xd$x) - gsub(/, -, levels(xd$x)) Christian On 04/15/2010 01:08 PM, David Winsemius wrote: On Apr 15, 2010, at 1:51 PM, prem_R wrote: Hi,every one .I have searched the solutions in the forum for replacing my date value which is in a data frame ,01/01/2000 to 01-01-2000 using replace function but got the following warning message x-2000/01/01 xd-as.data.frame(x) xd$x-replace(xd$x,xd$x==/,-) The replace function does not work with factors, it works with (complete) vectors, not substrings. It's also a real hassle to do such operations on factors, so just use character vectors and try gsub instead: x-2000/01/01 xd-as.data.frame(x, stringsAsFactors=FALSE) xd$x2-gsub(/,-, xd$x) xd x x2 1 2000/01/01 2000-01-01 Warning message: In `[-.factor`(`*tmp*`, list, value = -) : invalid factor level, NAs generated Is there any other method of doing it? or am i missing something?. please let me know if you need any more information. Thanks. Prem -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1911391.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. -- Christian Raschke Department of Economics and ISDS Research Lab (HSRG) Louisiana State University Patrick Taylor Hall, Rm 2128 Baton Rouge, LA 70803 cras...@lsu.edu __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
On Apr 15, 2010, at 2:22 PM, prem_R wrote: Thanks Mr.Winsemius for the proposed solution ,it worked fine.But when came to the entire data frame containing 40 rows ,i used the following code as proposed by you a$date1-gsub(/,-,a$date) got the following error: Error in `$-.data.frame`(`*tmp*`, date1, value = character(0)) : replacement has 0 rows, data has 441906 Please provide solution with the problem. Please provide sample data for the problem. Thanks. -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1914541.html Sent from the R help mailing list archive at Nabble.com. __ R-help@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 West Hartford, CT __ R-help@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.
Re: [R] Replace / with - in date
On Apr 15, 2010, at 2:28 PM, Christian Raschke wrote: Is there anything that speaks against just applying gsub to the factor levels if one would like to keep everything as factors (and not consider true Date classes or character vectors)? I.e: x - c(2000/01/01, 2001/02/01) xd - as.data.frame(x) levels(xd$x) - gsub(/, -, levels(xd$x)) Nothing. Other than the fact (which is not at all obvious to the new useRs) that it requires knowledge that the string representations are stored within the factor levels and not the factor values, and that operations on factors are often quite puzzling to the uninitiated. If one were to attempt applying a function that takes Date or Datetime arguments to such a date-like-factor, it is very likely that the initial results would be failures. The OP referred to the strings as a date value rather than as a factor level. I doubt that he realized the default operation of as.data.frame(). -- David. Christian On 04/15/2010 01:08 PM, David Winsemius wrote: On Apr 15, 2010, at 1:51 PM, prem_R wrote: Hi,every one .I have searched the solutions in the forum for replacing my date value which is in a data frame ,01/01/2000 to 01-01-2000 using replace function but got the following warning message x-2000/01/01 xd-as.data.frame(x) xd$x-replace(xd$x,xd$x==/,-) The replace function does not work with factors, it works with (complete) vectors, not substrings. It's also a real hassle to do such operations on factors, so just use character vectors and try gsub instead: x-2000/01/01 xd-as.data.frame(x, stringsAsFactors=FALSE) xd$x2-gsub(/,-, xd$x) xd x x2 1 2000/01/01 2000-01-01 Warning message: In `[-.factor`(`*tmp*`, list, value = -) : invalid factor level, NAs generated Is there any other method of doing it? or am i missing something?. please let me know if you need any more information. Thanks. Prem -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1911391.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. -- Christian Raschke Department of Economics and ISDS Research Lab (HSRG) Louisiana State University Patrick Taylor Hall, Rm 2128 Baton Rouge, LA 70803 cras...@lsu.edu __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
This is my sample data 2000/01/01 2000/01/01 2000/02/01 2000/10/01 2000/19/01 2000/20/01 2000/21/01 2000/22/01 2000/23/01 2000/25/01 2000/26/01 2000/27/01 2000/28/01 2000/29/01 Tried using levels function but got the following error . Error in levels(a$date) - gsub(/, -, levels(a$date)) : attempt to set an attribute on NULL Thanks. -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1934333.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
It's going to work better if you offer a non-ambiguous version of your data. Use dump or dput. If you use the dump route, then see the Posting Guide example. If you use dput, then it is as simple as dput(object). Perhaps (if dfrm is the name of a dataframe): dput(head(dfrm)) On Apr 15, 2010, at 5:27 PM, prem_R wrote: This is my sample data 2000/01/01 We cannot tell from the output whether that is a factor or a character vector. 2000/01/01 2000/02/01 2000/10/01 2000/19/01 2000/20/01 2000/21/01 2000/22/01 2000/23/01 2000/25/01 2000/26/01 2000/27/01 2000/28/01 2000/29/01 Tried using levels function but got the following error . Error in levels(a$date) - gsub(/, -, levels(a$date)) : attempt to set an attribute on NULL Thanks. -- David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
On Apr 15, 2010, at 5:46 PM, David Winsemius wrote: It's going to work better if you offer a non-ambiguous version of your data. Use dump or dput. If you use the dump route, then see the Posting Guide example. If you use dput, then it is as simple as dput(object). Perhaps (if dfrm is the name of a dataframe): dput(head(dfrm)) On Apr 15, 2010, at 5:27 PM, prem_R wrote: This is my sample data 2000/01/01 We cannot tell from the output whether that is a factor or a character vector. 2000/01/01 2000/02/01 2000/10/01 2000/19/01 2000/20/01 2000/21/01 2000/22/01 2000/23/01 2000/25/01 2000/26/01 2000/27/01 2000/28/01 2000/29/01 Tried using levels function but got the following error . Error in levels(a$date) - gsub(/, -, levels(a$date)) : attempt to set an attribute on NULL So it probably was not a factor variable despite what you offered in your previous example. The gsub function should be able to do the conversion if it's a character vector, as in this example: gsub(/,-, read.table(textConnection(2000/01/01 2000/01/01 2000/02/01 2000/10/01 2000/19/01 2000/20/01 2000/21/01 2000/22/01 2000/23/01 2000/25/01 2000/26/01 2000/27/01 2000/28/01 2000/29/01), header=FALSE, stringsAsFactors=FALSE)[,1] ) --- returns: [1] 2000-01-01 2000-01-01 2000-02-01 2000-10-01 2000-19-01 2000-20-01 [7] 2000-21-01 2000-22-01 2000-23-01 2000-25-01 2000-26-01 2000-27-01 [13] 2000-28-01 2000-29-01 Thanks. -- David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
x - c(2000/01/01, 2001/02/01,2000/03/01,2000/04/01,2000/05/01,2000/06/01,2000/07/01,2000/08/01,2000/09/01,2000/10/01) xd - as.data.frame(x) levels(xd$x) - gsub(/, -, levels(xd$x)) fix(xd) This works fine .but with one more variable say xsd in the data frame i'm getting the following error Error in levels(sa$date1) - gsub(/, -, levels(sa$date)) : attempt to set an attribute on NULL -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1934428.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
On Apr 15, 2010, at 7:20 PM, prem_R wrote: x - c(2000/01/01, 2001 / 02 / 01 ,2000 / 03 / 01 ,2000 / 04 / 01 ,2000 / 05 /01,2000/06/01,2000/07/01,2000/08/01,2000/09/01,2000/10/01) xd - as.data.frame(x) levels(xd$x) - gsub(/, -, levels(xd$x)) fix(xd) This works fine .but with one more variable say xsd in the data frame i'm getting the following error Error in levels(sa$date1) - gsub(/, -, levels(sa$date)) : attempt to set an attribute on NULL Cannot reproduce the error (and you are asked in the Posting Guide to include the code that creates the error rather than posting code that does not). x - c(2000/01/01, 2001 / 02 / 01 ,2000 / 03 / 01 ,2000 / 04 / 01 ,2000 / 05/01,2000/06/01,2000/07/01,2000/08/01,2000/09/01,2000/10/01) xd - data.frame(x=x, a=1) # creates another column in a. levels(xd$x) - gsub(/, -, levels(xd$x)) xd x a 1 2000-01-01 1 2 2001-02-01 1 3 2000-03-01 1 4 2000-04-01 1 5 2000-05-01 1 6 2000-06-01 1 7 2000-07-01 1 8 2000-08-01 1 9 2000-09-01 1 10 2000-10-01 1 sessionInfo() R version 2.10.1 RC (2009-12-09 r50695) x86_64-apple-darwin9.8.0 locale: [1] en_US.UTF-8/en_US.UTF-8/C/C/en_US.UTF-8/en_US.UTF-8 attached base packages: [1] splines stats graphics grDevices utils datasets methods base other attached packages: [1] adapt_1.0-4 Hmisc_3.7-0 survival_2.35-7 mapdata_2.1-1 maps_2.1-0 loaded via a namespace (and not attached): [1] cluster_1.12.1 grid_2.10.1lattice_0.18-3 tools_2.10.1 -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1934428.html Sent from the R help mailing list archive at Nabble.com. __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. David Winsemius, MD West Hartford, CT __ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] Replace / with - in date
On Apr 15, 2010, at 7:20 PM, prem_R wrote: x - c(2000/01/01, 2001 / 02 / 01 ,2000 / 03 / 01 ,2000 / 04 / 01 ,2000 / 05 /01,2000/06/01,2000/07/01,2000/08/01,2000/09/01,2000/10/01) xd - as.data.frame(x) levels(xd$x) - gsub(/, -, levels(xd$x)) fix(xd) This works fine .but with one more variable say xsd in the data frame i'm getting the following error Error in levels(sa$date1) - gsub(/, -, levels(sa$date)) : attempt to set an attribute on NULL Are there two columns date1 and date in sa? Have you made a typo? -- View this message in context: http://n4.nabble.com/Replace-with-in-date-tp1911391p1934428.html Sent from the R help mailing list archive at Nabble.com. __ R-help@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 West Hartford, CT __ R-help@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.
