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Date: Sat, 21 Feb 2015 15:06:39 -0500
Subject: Re: Algorithm for Creating Supersets of Smaller Sets Based on Common Elements
From: Joel Goldstick <joel.goldstick@gmail.com>
Cc: "python-list@python.org" <python-list@python.org>
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On Sat, Feb 21, 2015 at 2:46 PM, TommyVee <xxxxxxxx@xxxxxx.xxx> wrote:
> Start off with sets of elements as follows:
>
> 1. A,B,E,F
> 2. G,H,L,P,Q
> 3. C,D,E,F
> 4. E,X,Z
> 5. L,M,R
> 6. O,M,Y
>
> Note that sets 1, 3 and 4 all have the element 'E' in common, therefore they
> are "related" and form the following superset:
>
> A,B,C,D,E,F,X,Z
>
> Likewise, sets 2 and 5 have the element 'L' in common, then set 5 and 6 have
> element 'M' in common, therefore they form the following superset:
>
> G,H,L,M,O,P,Q,R,Y
>
> I think you get the point.  As long as sets have at least 1 common element,
> they combine to form a superset.  Also "links" (common elements) between
> sets may go down multiple levels, as described in the second case above
> (2->5->6).  Cycles thankfully, are not possible.
>
> BTW, the number of individual sets (and resultant supersets) will be very
> large.
>
> I don't know where to start with this.  I thought about some type of
> recursive algorithm, but I'm not sure.  I could figure out the Python
> implementation easy enough, I'm just stumped on the algorithm itself.
>
> Anybody have an idea?
>

start with reading about python sets.  If you take the intersection of
two sets it will return a set with common elements.  If that is empty,
they don't pass your test.  If you take the union, you get a set with
the set values in each.


> Thanks, Tom
> --
> https://mail.python.org/mailman/listinfo/python-list



-- 
Joel Goldstick
http://joelgoldstick.com