Merging two columns into one in R

Question

I have the following data frame, and am trying to merge the two columns into one, while replacing NA\'s with the numeric values.

ID    A     B
1         


        

Answer 1

You can use unite from tidyr:

library(tidyr)

df[is.na(df)] = ''
unite(df, new, A:B, sep='')
#  ID new
#1  1   3
#2  2   2
#3  3   4
#4  4   1