From curtisb@mrc.ac.za Thu Jun  3 02:45:31 1999
Received: from mxu4.u.washington.edu (mxu4.u.washington.edu [140.142.33.8])
	by lists.u.washington.edu (8.9.3+UW99.02/8.9.3+UW99.01) with ESMTP id CAA38864
	for <waphgis@lists.u.washington.edu>; Thu, 3 Jun 1999 02:45:31 -0700
Received: from mordor.mrc.ac.za (mordor.mrc.ac.za [196.25.195.194])
	by mxu4.u.washington.edu (8.9.3+UW99.02/8.9.3+UW99.01) with ESMTP id CAA26032
	for <waphgis@u.washington.edu>; Thu, 3 Jun 1999 02:45:28 -0700
Received: (from nobody@localhost) by mordor.mrc.ac.za (8.8.8/8.6.9) id LAA28723 for <waphgis@u.washington.edu>; Thu, 3 Jun 1999 11:45:19 +0200 (SAST)
Received: by mordor via recvmail id 28700; Thu Jun  3 11:45:16 1999
From: "Bronwyn Curtis" <curtisb@mrc.ac.za>
To: waphgis@u.washington.edu
Date: Thu, 3 Jun 1999 11:43:14 +0000
MIME-Version: 1.0
Content-type: text/plain; charset=US-ASCII
Content-transfer-encoding: 7BIT
Subject: (Fwd) Re: Adjacency Matrix
Reply-to: curtisb@mrc.ac.za
X-pmrqc: 1
Message-ID: <19990603094138892.AAA141.323@mrc.ac.za>

Hi!

I am forwarding the answer I got when I posed the same question. It 
works well and hope it is what you are looking for! 

Regards

Bronwyn

THIS IS THE USER'S QUESTIO
>Hello, I am a user of Mapinfo Professional.
>
>Could you teach me how to do the followings?;
>
>(Q1)I have a polygonal map table.
>
>From this, I would like to generate such a matrix
>as shows which polygones are adjacent to each other,
>and which are not. For example;
>
>                       WA  NT  SA  QL NS
>Western_Australia(WA)      0   0   1  1
>Northern_Territory(NT)         0   0  0
>South_Australia(SA)                0  0
>Queensland(QL)                        0
>New_Southwales(NS)
>
>Where 0 indicates adjacency, and 1 indicates non_adjacency.
>
>Can I make such a matrix(text file) by using Mapinfo command,
>or processing mapinfo data file by in-house programme?
>

AND THE ANSWER

Hi,

I was solving a similar problem in the following steps:

1. made a column in the table with rowid (using update column) named, say,
record#.
2. if original table had a name of mytable, then made a copy of it, named
say - copyofmytable, and opened it
3. made the following query using mapbasic window:

Select mytable.record#, copyofmytable.record#, AreaOverlap(mytable.obj,
copyofmytable.obj)>0 from
mytable, copyofmytable where mytable.obj Intersects copyofmytable.obj and
mytable.record#<>copyofmytable.record# into adjacency
Browse * From adjacency

Adjacency table contains a pairwise listing of adjacent polygons, which can
be crosstabulated in any database management system.

hope this helps

Mikhail


Spatial Technologiesr

            Assisting You make faster, more informed decisions
            through the power of spatial analysis.
            __________________________________
            Box 343 Rivonia 2128 South Africa
            Voice: (2711) 807 3807 Fax: (2711) 803 0010

Health GIS Centre
Medical Research Council
P O Box 17120
Congella
Durban
4013
South Africa
Tel: 031-2051481
Fax: 031-2051498
.