Method shuffle

src/danfojs-base/shared/utils.ts:618–631

* Shuffles and returns a random slice of an array * @param num * @param array

(array: ArrayType1D | ArrayType2D, num: number)

     * @param array 
     */
    shuffle(array: ArrayType1D | ArrayType2D, num: number): ArrayType1D | ArrayType2D {
        let i = array.length;
        let j = 0;
        let temp;

        while (i--) {
            j = Math.floor(Math.random() * (i + 1));
            temp = array[i];
            array[i] = array[j];
            array[j] = temp;
        }

        return array.slice(0, num);
    }

    /**
     * Sorts an array in specified order