def descents(self):
        """
        Returns the positions of descents in a permutation, ie, the location
        where p[i] > p[i+1]

        Examples
        ========

        >>> p = Permutation([4, 0, 1, 3, 2])
        >>> p.descents()
        [0, 3]

        See Also
        ========

        ascents, inversions, min, max

        """
        a = self.array_form
        pos = [i for i in range(len(a) - 1) if a[i] > a[i + 1]]
        return pos