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rregexgsubsubstr

How to fill all rows in a column with data from other columns?

I have a dataset called 'names' as shown below. The 'expected.entry.in.this.col' column is currently empty, but below I have shown how it should look. How can I write the logic?

Basically I think I'll need to run a loop through every row and for each row, use an 'if' condition to check the format and then enter the data into 'expected.entry.in.this.col' appropriately. How would I go about doing this? (a bit unfamiliar with R syntax for these kind of tasks).

names

enter image description here

EDIT: row 3 is a mistake and should read williams.harry

Solution

  • try something like this:

    df <- data.frame(first = c("Kevin", "Megan"), last = c("Spacey", "Fox"),
                 format = c("f.last", "F.L."))

df$new <- NA
df$new <- ifelse(df$format == "f.last",
                 tolower(paste0(substr(df$first,1,1),".",df$last)),
                 df$new)
df$new <- ifelse(df$format == "F.L.",
                 paste0(substr(df$first,1,1),".", substr(df$last,1,1)),
                 df$new)

df

  first   last format      new
1 Kevin Spacey f.last k.spacey
2 Megan    Fox   F.L.      M.F