SNV Krishna
2011-Apr-06 08:45 UTC
[R] syntax to subset for multiple values from a single variable
Hi All, Is it possible to use the subset() function to select data based on multiple values of a single variable from a data frame. My actual data set is much bigger and would like to illustrate with following dataset> df = data.frame(x = c('a','b','c','d','e','f','g','h','a','a','b','b'), y= 1:12) I would like to select all rows where x = a or b.> subset(df, x == c('a','b')) # this command did not return all rows where xis equal to a or b x y 1 a 1 2 b 2 9 a 9 12 b 12> df[df$x %in% c('a','b'),] # subsetting using subscripts returned all rowsx y 1 a 1 2 b 2 9 a 9 10 a 10 11 b 11 12 b 12 I know there might be a problem with subset syntax that I have used, but could'nt figure out what it is. Any insights from members will be highly appreciated and thanks for the same. Regards, S.N.V. Krishna [[alternative HTML version deleted]]
Ivan Calandra
2011-Apr-06 09:38 UTC
[R] syntax to subset for multiple values from a single variable
Hi, I'm not sure what you're looking for because it looks to me that you have the answer already... Is this what you want: subset(df, x %in% c('a','b')) ? Ivan Le 4/6/2011 10:45, SNV Krishna a ?crit :> Hi All, > > Is it possible to use the subset() function to select data based on multiple > values of a single variable from a data frame. > > My actual data set is much bigger and would like to illustrate with > following dataset >> df = data.frame(x = c('a','b','c','d','e','f','g','h','a','a','b','b'), y > = 1:12) > I would like to select all rows where x = a or b. > > >> subset(df, x == c('a','b')) # this command did not return all rows where x > is equal to a or b > > x y > > 1 a 1 > > 2 b 2 > > 9 a 9 > > 12 b 12 > >> df[df$x %in% c('a','b'),] # subsetting using subscripts returned all rows > x y > > 1 a 1 > > 2 b 2 > > 9 a 9 > > 10 a 10 > > 11 b 11 > > 12 b 12 > > I know there might be a problem with subset syntax that I have used, but > could'nt figure out what it is. Any insights from members will be highly > appreciated and thanks for the same. > > Regards, > > S.N.V. Krishna > > > > [[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. >-- Ivan CALANDRA PhD Student University of Hamburg Biozentrum Grindel und Zoologisches Museum Abt. S?ugetiere Martin-Luther-King-Platz 3 D-20146 Hamburg, GERMANY +49(0)40 42838 6231 ivan.calandra at uni-hamburg.de ********** http://www.for771.uni-bonn.de http://webapp5.rrz.uni-hamburg.de/mammals/eng/1525_8_1.php