I'm looking for a two-digit number that comes before the word "years" and a seven- or eight-digit number that comes after the word "years." An example of the data is shown below.

data <- "mr john is 45 years old his number is 12345678, mr doe is 57 years 7654321"

data <- as.list(data)

I tried this approach and was successful in getting two digit numbers before the word "years" :

stringr::str_extract_all(data,regex(".\\d{2}\\s(?:year)"))

I also tried this method to get the number after word "years" :

str_extract_all(data,regex(".\\d{2}\\s(?:year).\\d{7,8}"))

I managed to get the number that appear directly after the word years :

" 57 year 7654321"

However, I was unsuccessful in getting eight digit numbers following the word "years" that included other characters in between the number and the word "years".

How can I retrieve the number only after the word "years" by skipping this other word/character?

I really appreciate your help

CodePudding user response：

We may use str_replace to match and remove the non-digits before and after the 'years' and then extract the digits before and after the years including the 'years'

library(stringr)
str_extract_all(str_replace_all(data,
     "(?<=years)\\D |(\\D )(?=years)", " "), "\\d{2}\\s years\\s \\d{7,8}")[[1]]
[1] "45 years 12345678" "57 years 7654321" 

Or another option is to capture the digits, along with the 'years' substring with str_match and then paste them together

library(purrr)
library(dplyr)
str_match_all(data, "(\\d{2})\\D (years)\\D (\\d{7,8})")[[1]][,-1] %>% 
     as.data.frame %>% 
     invoke(str_c, sep =" ", .)
[1] "45 years 12345678" "57 years 7654321" 

data

data <- "mr john is 45 years old his number is 12345678, mr doe is 57 years 7654321"

CodePudding user response：

Here is a base R approach:

1. Create a list with strsplit separating by ,
2. define a function my_func that takes a string and searches for numeric before year and after year and then pastes all together.
3. Use lapply to apply your function to the list.
4. Use toString() to get the expected output.

my_list <- strsplit(data, ",")

my_func <- function(x){
a <- as.integer(sub(".*?(\\d )\\s*year.*", "\\1", x))
b <- as.integer(sub(".*?year.*?(\\d ).*", "\\1", x))
paste(a, "year", b)
}

result <- lapply(my_list, my_func)
lapply(result, toString)

Output:

[[1]]
[1] "45 year 12345678, 57 year 7654321"