Flat list to matrix

listToMatrix.ts

  /**
   * Convert a flat list into a 2D Array.
   *
   * @param list Flat list.
   * @param elementsPerSubArray Size of inner arrays.
   * @returns 2D array of the given size..
   */
  private listToMatrix<T>(list: T[], elementsPerSubArray: number): T[][] {
    const matrix: T[][] = [];
    let index;
    let k;

    for (index = 0, k = -1; index < list.length; index++) {
      if (index % elementsPerSubArray === 0) {
        k++;
        matrix[k] = [] as T[];
      }

      matrix[k].push(list[index] as T);
    }

    return matrix;
  }