grouping elements of a data frame
On Jan 15, 2013, at 9:10 AM, Nuri Alpay Temiz wrote:
Hi everyone,
I have a question on selecting and grouping elements of a data frame. For example:
A.df<- [ a c 0.9
b x 0.8
b z 0.5
c y 0.9
c x 0.7
c z 0.6]
That is not R code. Matlab?, Python?
I want to create a list of a data frame that gives me the unique values of column 1 of A.df so that i can create intersects. That is:
B[a]<- [ c 0.9]
B[b]<- [ x 0.8
z 0.5]
B[c]<- [ y 0.9
x 0.7
z 0.6]
B[c] n B[b] <- c(x,z)
That's some sort of coded message? We are supposed to know what the "n" operation will do when assigned a vector? Assuming your really do have a dataframe named B: intersect(B$c, B$b) Please code up examples in R in the future.
David Winsemius Alameda, CA, USA