def dmp_diff_in(f, m, j, u, K):
    if j < 0 or j > u:
        raise IndexError("0 <= j <= %s expected, got %s" % (u, j))

    return _rec_diff_in(f, m, u, 0, j, K)
``m``-th order derivative in ``x_j`` of a polynomial in ``K[X]``.
dataset/ETHPy150Open sympy/sympy/sympy/polys/densetools.py/dmp_diff_in