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rstrsplit

How to split letters with bracket and numbers in R?

The string is s = '[12]B1[16]M5'

I want to split it as the following results with strsplit function in R:

let <- c('[12]B', '[16]M')

num <- c(1, 5)

Thanks a lot

Solution

  • You could use regular expression for your task.

    s = '[12]B1[16]M22'

grx <- gregexpr("\\[.+?\\].+[[:digit:]]?",  s)
let <- do.call(c, regmatches(s, grx))

#let
#[1] "[12]B" "[16]M"

    If you want to get all chunks (let + num), you can tweak the patter as below. This facilitates extracting the numeric part.

    grx <- gregexpr("\\[.+?\\].+([[:digit:]]+)",  s)
out <- do.call(c, regmatches(s, grx))

num <- gsub(".+\\][[:alpha:]]+", "", out)

num
[1] "1"  "22"