/**
 * Jaccard Index
 * src/metric/Jaccard.ts
 *
 * @see https://en.wikipedia.org/wiki/Jaccard_index
 *
 * The Jaccard Index (or Jaccard similarity coefficient) measures the similarity
 * between two sets by dividing the size of their intersection by the size of
 * their union. In string similarity, it is often used to compare sets of characters,
 * tokens, or n-grams. The result is a value between 0 and 1, where 1 means the
 * sets are identical and 0 means they have no elements in common.
 *
 * @module Metric
 * @name JaccardIndex
 * @author Paul Köhler (komed3)
 * @license MIT
 */
import type { MetricInput, MetricOptions, MetricCompute } from '../utils/Types';
import { Metric } from './Metric';
export interface JaccardRaw {
    intersection: number;
    union: number;
}
/**
 * JaccardIndex class extends the Metric class to implement the Jaccard Index algorithm.
 */
export declare class JaccardIndex extends Metric<JaccardRaw> {
    /**
     * Constructor for the JaccardIndex class.
     *
     * Initializes the Jaccard Index metric with two input strings or
     * arrays of strings and optional options.
     *
     * Metric is symmetrical.
     *
     * @param {MetricInput} a - First input string or array of strings
     * @param {MetricInput} b - Second input string or array of strings
     * @param {MetricOptions} [opt] - Options for the metric computation
     */
    constructor(a: MetricInput, b: MetricInput, opt?: MetricOptions);
    /**
     * Calculates the Jaccard Index between two strings.
     *
     * @param {string} a - First string
     * @param {string} b - Second string
     * @param {number} m - Length of the first string
     * @param {number} n - Length of the second string
     * @return {MetricCompute< JaccardRaw >} - Object containing the similarity result and raw values
     */
    protected compute(a: string, b: string, m: number, n: number): MetricCompute<JaccardRaw>;
}