[R] how to split row elements [1] and [2] of a string variable A via srtsplit and sapply

[aldi]

Hi,
I have a data.frame x1, of which a variable A needs to be split by 
element 1 and element 2 where separator is ":". Sometimes could be three 
elements in A, but I do not need the third element.

Since R does not have a SCAN function as in SAS, C=scan(A,1,":"); 
D=scan(A,2,":");
I am using a combination of strsplit and sapply. If I do not use the 
index [i] then R captures the full vector . Instead I need row by row 
capturing the first and the second element and from them create two new 
variables C and D.
Right now as is somehow in the loop i C is captured correctly, but D is 
missing because the variables AA does not have it. Any suggestions? 
Thank you in advance, Aldi

A          B
1:29439275 0.46773514
5:85928892 0.81283052
10:128341232 0.09332543
1:106024283:ID 0.36307805
3:62707519 0.42657952
2:80464120 0.89125094

x1<-read.table(file='./test.txt',head=T,sep='\t')
x1$A <- as.character(x1$A)

for(i in 1:length(x1$A)){

x1$AA[i] <- as.numeric(unlist(strsplit(x1$A[i],':')))

x1$C[i] <- sapply(x1$AA[i],function(x)x[1])
x1$D[i] <- sapply(x1$AA[i],function(x)x[2])
}

x1



 > x1
                A          B AA  C  D
1     1:29439275 0.46773514  1  1 NA
2     5:85928892 0.81283052  5  5 NA
3   10:128341232 0.09332543 10 10 NA
4 1:106024283:ID 0.36307805  1  1 NA
5     3:62707519 0.42657952  3  3 NA
6     2:80464120 0.89125094  2  2 NA


-- 


	[[alternative HTML version deleted]]