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rstring-concatenationdata-manipulation

Concatenation between rows

I have a dataframe with two colmns: 

C1 <- c("abcd > de > efg", "hij > kl > iiii", "aa", "a > bbb")
C2 <- c("1980","1982","1989","1989")

df <- data.frame(C1, C2, stringsAsFactors = FALSE)

My goal is concatenate the arguments of the 2 of them like this:

result <- c("1980abcd > 1980de > 1980efg", "1982hij > 1982kl > 1982iiii", "1989aa", "1989a > 1989bbb")

How can i do that? Thanks.

Solution

  • One way via base R is to use split the C1 vector and use mapply to paste with C2, i.e.

    v1 <- mapply(function(x, y) paste(paste0(x, y), collapse = ' > '), C2, strsplit(C1, ' > '))

unname(v1)
#[1] "1980abcd > 1980de > 1980efg" "1982hij > 1982kl > 1982iiii" "1989aa"   "1989a > 1989bbb"

    NOTE: The result of mapply (i.e. v1) is a named vector. Hence I used unname to get to your desired structure. However, note that a named vector is still a vector and will behave as such.