Re: [R] How to retrieve a column name of a data frame

2012-02-02 Thread R. Michael Weylandt
I'd use something like which(df == "b", arr.ind = TRUE) which, gives the column number in the second spot; this gives you colnames(df)[which(df == "b", arr.ind = TRUE)[2]] Michael On Thu, Feb 2, 2012 at 11:00 AM, ikuzar wrote: > Sorry, it was not clear: > > my program have to return column n

Re: [R] How to retrieve a column name of a data frame

2012-02-02 Thread ikuzar
Sorry, it was not clear: my program have to return column name corresponding to a value, for example 'b' (so, the corresponding column is c1) How to retrieve c1 ? Thanks -- View this message in context: http://r.789695.n4.nabble.com/How-to-retrieve-a-column-name-of-a-data-frame-tp4351764p435186

Re: [R] How to retrieve a column name of a data frame

2012-02-02 Thread Rainer Schuermann
> colnames( df )[2] [1] "c2" On Thursday 02 February 2012 07:31:33 ikuzar wrote: > Hi, > > I 'd like to know how to retrieve a column name of a data frame. For > instance : > > df = data.frame(c1=c('a','b'),c2=c(1,2)) > > > df > > c1 c2 > 1 a 1 > 2 b 2 > > I would like to retrieve th

Re: [R] How to retrieve a column name of a data frame

2012-02-02 Thread R. Michael Weylandt
colnames(df)[2] Michael On Thu, Feb 2, 2012 at 10:31 AM, ikuzar wrote: > Hi, > > I 'd like to know how to retrieve a column name of a data frame. For > instance : > > df = data.frame(c1=c('a','b'),c2=c(1,2)) >> df >  c1 c2 > 1  a  1 > 2  b  2 > > I would like to retrieve the column name which va