r - Concatenate String with Variables

Question

Input dataset is like:

test = data.frame(Var_a = c("A|B","C|D|E","F"),Var_b = c("X"))

Desired output dataset is like:

test1 = data.frame(Var_C = c("AX|BX","CX|DX|EX","FX"))

Answer 1

Here's a base R option :

splitting the string on |, pasting each word with corresponding Var_b value and collapsing the string back.

test$Var_c <- mapply(function(x, y) paste0(x, y, collapse = '|'), 
                 strsplit(test$Var_a, '|', fixed = TRUE), test$Var_b)

test

#  Var_a Var_b    Var_c
#1   A|B     X    AX|BX
#2 C|D|E     X CX|DX|EX
#3     F     X       FX