Hi all, I have a numeric vector with 1 decimal place, and I'd like to extract the last 3 characters, including the decimal point. The vector ranges from 0 to 20. x <- round(runif(100)*20, digits=1) Some of numbers have 3 characters, and some have 4. I've read up on the substr() function but that extracts characters based on exact positions. How can I extract just the last 3 characters no matter the length of the number? e.g. from 16.7 I want 6.7, from 3.5 I want 3.5 as it is. Thanks, Kang Min
You can use nchar() to get the length of the string, and use that in substring: mynum <- as.character(15.6)> substring(mynum, nchar(mynum)-2, nchar(mynum))[1] "5.6" On Sun, Dec 4, 2011 at 8:38 AM, Kang Min <ngokangmin at gmail.com> wrote:> Hi all, > > I have a numeric vector with 1 decimal place, and I'd like to extract > the last 3 characters, including the decimal point. The vector ranges > from 0 to 20. > > x <- round(runif(100)*20, digits=1) > > Some of numbers have 3 characters, and some have 4. I've read up on > the substr() function but that extracts characters based on exact > positions. How can I extract just the last 3 characters no matter the > length of the number? e.g. from 16.7 I want 6.7, from 3.5 I want 3.5 > as it is. > > Thanks, > Kang Min >-- Sarah Goslee http://www.functionaldiversity.org
On 04.12.2011 14:38, Kang Min wrote:> Hi all, > > I have a numeric vector with 1 decimal place, and I'd like to extract > the last 3 characters, including the decimal point. The vector ranges > from 0 to 20. > > x<- round(runif(100)*20, digits=1)formatC(round(x%%10, 1), format="f", digits=1) Uwe Ligges> Some of numbers have 3 characters, and some have 4. I've read up on > the substr() function but that extracts characters based on exact > positions. How can I extract just the last 3 characters no matter the > length of the number? e.g. from 16.7 I want 6.7, from 3.5 I want 3.5 > as it is. > > Thanks, > Kang Min > > ______________________________________________ > 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.