Compute the median of an array, ignoring NaNs.

        :param a: The array.
        :return: The median value of the array.

def fn_median(self, a, axis=None):
        """
        Compute the median of an array, ignoring NaNs.

        :param a: The array.
        :return: The median value of the array.
        """

        return numpy.nanmedian(self._to_ndarray(a), axis=axis)