[R] indexing in data frames

arun smartpink111 at yahoo.com
Thu Aug 9 23:39:08 CEST 2012


HI,

In the reply I sent, I forgot to add,

anew<-list()#before,
for(i in 1:length(b1)){
 anew[[i]]<-list()
 anew[[i]]<-b1[[i]]-c[[i]]
 }

A.K.

----- Original Message -----
From: jimi adams <jadams at american.edu>
To: r-help at r-project.org
Cc: 
Sent: Thursday, August 9, 2012 4:42 PM
Subject: [R] indexing in data frames

I'm still not fully understanding exactly how R is handling data frames, but am getting closer. Any help with this one will likely go a long way in getting me there. Let's say I have a data frame, let's call it "a". Within that data frame i have two variables, let's call them "b" and "c", where "b" is a single numeric value per observation, while "c" is a LIST of numeric values. What I want to be able to do is perform an operation on each element in "c" by the single element in "b". 

So, for example, if I wanted to subtract each element in "c" from the scalar in "b". For example, if i had

> a$b
[1] 1988
[2] 1989
…
& 
> a$c
[[1]]
[1] 1985 1982 1984
[[2]]
[1] 1988 1980
…

I'm looking for a result of:
a$new
[[1]]
[1] 3 6 4
[[2]]
[1] 1 9
…

I've tried a few different things, none of which have the desired result. Any help appreciated.
thanks!

jimi adams
Assistant Professor
Department of Sociology
American University
e: jadams at american.edu
w: jimiadams.com

______________________________________________
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.




More information about the R-help mailing list