ReadabilityFramework/Sources/Readability/Scorers/FleschKincaidGrade.swift
2022-05-20 12:45:26 +08:00

28 lines
897 B
Swift

//
// File.swift
// Readability
//
// Created by Shibo Lyu on 2022/5/20.
//
import Foundation
struct RAFleschKincaidGradeScorer: RAScorer {
static let requiresCommonMetrics: Set<RACommonMetric>? = [
.avgWordsPerSentence,
.avgSyllablesPerWord
]
static let meta = RAScorerMeta(
name: "Flesch-Kincaid Grade",
creator: "John P. Kincaid",
citation: "Kincaid, J. P., Fishburne Jr, R. P., Rogers, R. L., & Chissom, B. S. (1975). Derivation of new readability formulas (automated readability index, fog count and flesch reading ease formula) for navy enlisted personnel. Naval Technical Training Command Millington TN Research Branch."
)
func score(_ text: String, metrics: RACommonMetricsCalculator.Results?) -> Double {
let asl = metrics![.avgWordsPerSentence]!
let asw = metrics![.avgSyllablesPerWord]!
return (0.39 * asl) + (11.8 * asw) - 15.59
}
}