moving-ngrams.ts

import { A, F } from "@mobily/ts-belt";

// // Function to generate moving n-grams

export const movingNgrams = (words: string[]): string[][][] => {
  if (words.length === 0) {
    return [];
  }
  const results: string[][][] = [];

  // Helper function to generate partitions
  const generatePartitions = (start: number, current: string[][]): void => {
    if (start >= words.length) {
      results.push([...current]);
      return;
    }

    // Try different n-gram sizes starting from this position
    for (let size = 1; start + size <= words.length; size++) {
      const ngram = words.slice(start, start + size);
      current.push(ngram);
      generatePartitions(start + size, current);
      current.pop();
    }
  };

  generatePartitions(0, []);
  const unique = F.toMutable(A.uniqBy(results, (r) => JSON.stringify(r)));
  return unique;
};