carmakes.R

library(dplyr)

# If we don't have 'TOYOTA PRADO' in the set?

test <- c('ROVER', 'CRUISER', 'TOYOTA', 'TOYOTA PRADO', 'NISSAN')

old <- c('ROVER', 'CRUISER', 'TOYOTA')
new <- c('LandRover', 'LandRover', 'Toyota')

lookup <- data.frame(old, new)

data <- data.frame(DESCRIPTION = sample(test, 30, replace = TRUE))



categorise <- function(x){
  i <- which(sapply(lookup$old, function(y) grepl(y, x)))
  if(length(i) == 0) i <- NA
  return(i)
}

data <- data %>% 
  mutate(make = 
    lookup$new[sapply(data$DESCRIPTION, categorise)]
  )