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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