Method sortArrayByIndex

src/danfojs-base/shared/utils.ts:744–755

* Returns the index of a sorted array * @param arr1 The first array * @param arr2 The second array * @param dtype The data type of the arrays * * @returns sorted index

(arr1: ArrayType1D | ArrayType2D, arr2: ArrayType1D | ArrayType2D, dtype: string)

     * @returns sorted index
     */
    sortArrayByIndex(arr1: ArrayType1D | ArrayType2D, arr2: ArrayType1D | ArrayType2D, dtype: string) {
        const sortedIdx = arr1.map((item, index) => {
            return [arr2[index], item];
        });
        if (dtype == "string") {
            sortedIdx.sort();
        } else {
            sortedIdx.sort(([arg1], [arg2]) => (arg2 as unknown as number) - (arg1 as unknown as number));
        }

        return sortedIdx.map(([, item]) => item) as number[]
    }

    /**
     * Returns a new series with properties of the old series