[postgis-users] How to translate DE-9IM codes of the st_relation() function?

[Peter Padua Krauss]

Hello,

I need a function that translates a st_relation() result into a
human-readable string, like this (translations):

 'FF2FF1212' = "Disjoint"

 'FF2F01212' = "Intersects (in a point) and Touches (in a point)"

 'FF1F0F1F2' or 'FF10F0102' or 'FF1F0F1F2' can be understand as
                 "Intersects and Touches".

 '0FFFFFFF2' = "Equals (points)"

 '1FFFFFFF2' = "Equals (lines)"

 '0FFFFF0F2' = "Intersects, Crosses, Within and CoveredBy"
  ...

This function exist?

The same question is explained with some more details and  examples at
http://gis.stackexchange.com/q/26124/7505

---- ----

In its most general form the DE-9IM model is quite complex, so to make it
usable,
the adoption of "named predicates" have been specified: ST_Intersects,
ST_Disjoint,
ST_Touches, ST_Equals, ST_Within, etc.

Programmers can express "topological queries" with these predicates.

But "mortal programmers" can't interpret DE-9IM codes of a single
ST_Relate(A,B)
returned string, or, even less, a list of them... The programmer need
human-readable
expression, like the predicates, and need also some summarization
(for usual applications there are so many semantic equivalences between
DE-9IM codes).

----- -----

There are a PostGIS library or module (perhaps into the PostGIS's 2.0
Topology new module)
with a tool to translate DE-9IM into predicates?
If there are not: may be we discuss here the possibility to develop that
kind of translator function?


Thanks,

PPKrauss
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