Applies a reduce function to all ViewableElement objects.

        See :py:meth:`Dimensioned.opts` and :py:meth:`Apply.__call__`
        for more information.

def reduce(self, dimensions=[], function=None, spreadfn=None, **kwargs):
        """Applies a reduce function to all ViewableElement objects.

        See :py:meth:`Dimensioned.opts` and :py:meth:`Apply.__call__`
        for more information.
        """
        kwargs['_method_args'] = (dimensions, function, spreadfn)
        return self.__call__('reduce', **kwargs)