Function rational_add

numpy/core/src/umath/_rational_tests.c:195–203

}

static inline rational
rational_add(rational x, rational y) {
    /*
     * Note that the numerator computation can never overflow int128_t,
     * since each term is strictly under 2**128/4 (since d > 0).
     */
    return make_rational_fast((npy_int64)x.n*d(y)+(npy_int64)d(x)*y.n,
        (npy_int64)d(x)*d(y));
}

static inline rational
rational_subtract(rational x, rational y) {