Issue #7537: Add is_disjoint() method and an alias isdisjoint()

Add a method for finding if two sets are disjoint.
On Sat, Jun 7, 2014 at 7:39 AM, Randy <notifications@github.com> wrote:
>
> In sympy/sets/sets.py:
>
> > +        Returns 'True' if 'self' and 'other' are disjoint
> > +
> > +        >>> from sympy import Interval
> > +        >>> Interval(0, 2).is_disjoint(Interval(1, 2))
> > +        False
> > +        >>> Interval(0, 2).is_disjoint(Interval(3, 4))
> > +        True
> > +
> > +        References
> > +        ==========
> > +
> > +        http://en.wikipedia.org/wiki/Disjoint_sets
> > +        """
> > +        return self.intersect(other) == S.EmptySet
> > +
> > +    def isdisjoint(self, other):
>
> I think it does. I'm guessing based off of the docs for Relational, which do show Rel etc. even though they're just class aliases. I would hope Sphinx does the same for method aliases, but I don't know for sure.


It does create the API doc, but it creates the *same* API doc as
is_disjoint() including the docstring, et. al.

So, i think we will best leave it as it is.