words / dale-chall-formula Goto Github PK

According to the Wikipedia page, the formula was supposed to also include words with other suffixes.
I found a details on allowed suffixes here:
http://www.lefthandlogic.com/htmdocs/tools/okapi/okapimanual/dale_challWorksheet.PDF

That also says that numbers are allowed, and that the formula is refers to counting multiples of difficult words, so it appears that the uniqueness of easy words need not be considered, but just the total.

I've switched my readability to have the following, but I think these details would likely be better as a isDifficult method in dale-chall-formula. Doing so would mean dale-chall-formula would have to require dale-chall word list, which you perhaps wanted to avoid.

let reDaleChallEndings = /(s|ing|n|ed|ly|er|est)$/
let reDaleChallNumber = /^[1-9]\d{0,2}(,?\d{3})*$/
`

if (
  daleChall.includes(normalized) ||
  normalized.match(reDaleChallNumber) ||
  (normalized.match(reDaleChallEndings) &&
    daleChall.includes(stemmer(normalized)))
) {
  easyWordCount++
}

`

It appears that in order to use this module, I need to come up with my own count of "difficult words", but I have no idea how to do that. Is there a particular dictionary I should be using? Does a program exist to compare words against that dictionary? Or is that something that needs to be built in order to use this formula?