From: Surfing <onlinesurfing@gmail.com>
To: pgsql-sql@postgresql.org
Subject: Euclidean distance between two sets of tuples
Date: Mon, 25 Feb 2013 19:34:10 +0100
Message-ID: <512BAEA2.9040803@gmail.com> (raw)
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Hi all,
I would like to ask if there exists a function to calculate the
Euclidean distance between two rows of the same table.
Obviously, the distance between two non-numeric fields should be 0 if
they are the same value, 1 otherwise.
In general, I need to compute an average distance between the subsets of
rows, computed pairwise.
Example:
- Set 1: 10 rows
- Set 2: 15 rows
- Distances computed 150
I just need the value 1/150*(Sum of all the computed Euclidean distances).
I could write a procedure, but it would be nice if there already exists
a function which at least computes a single Euclidean function between
two rows.
Any suggestion?
Thank you.
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To: pgsql-sql@postgresql.org
Cc: onlinesurfing@gmail.com
Subject: Re: Euclidean distance between two sets of tuples
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