se of `ncfdtr` with respect to `f`.
    ncfdtridfd : Inverse of `ncfdtr` with respect to `dfd`.
    ncfdtridfn : Inverse of `ncfdtr` with respect to `dfn`.

    Examples
    --------
    >>> from scipy.special import ncfdtr, ncfdtrinc

    Compute the CDF for several values of `nc`:

    >>> nc = [0.5, 1.5, 2.0]
    >>> p = ncfdtr(2, 3, nc, 15)
    >>> p
    array([ 0.96309246,  0.94327955,  0.93304098])

    Compute the inverse. We recover the values of `nc`, as expected:

    >>> ncfdtrinc(2, 3, p, 15)
    array([ 0.5,  1.5,  2. ])

    Ú