I’m trying to merge/join the two dataframes df and df2.

df was generated from a character vector that was cut at each position (4th, 10th, 12th, … character) into string. The initial vector looked like this

vec1 <- paste(df$string, collapse = "").

df2 has name that correspond to some of the characters in vec1. For instance, the third and fifth characters in vec1 are P and A, and their names are pear and apple, respectively.

df <- data.frame("position" = c(4, 10, 12, 20, 27, 30),
             "string" = c("MPPA", "APARLA", "LA", "LGLGLWLG", "ALAGGPG", "RGC"))
df2 <- data.frame("character" = c("P", "A", "L", "A", "P", "G"),
              "position" = c(3, 5, 9, 21, 26, 29),
              "name" = c("pear", "apple", "lemon", "apricot", "peach", "grape"))

I want to combine df and df2 into df3 to show which string in df has name, like below. What would be a good way to do this?

df3 <- data.frame("position" = c(4, 10, 12, 20, 27, 30),
              "string" = c("MPPA", "APARLA", "LA", "LGLGLWLG", "ALAGGPG", "RGC"),
              "name" = c("pear", "apple, lemon", NA, NA, "apricot, peach", "grape"))