Ticket #209 (closed patch: fixed)
Discrete Hausdorff distance implementation (through GEOS)
|Reported by:||vincentp||Owned by:||pramsey|
|Keywords:||hausdorff distance geos||Cc:|
JTS and GEOS have a discrete Hausdorff distance algorithm. It is currently not exposed in GEOS C API, nor in PostGIS. A patch for GEOS is available to expose these functions : http://trac.osgeo.org/geos/ticket/264
Please find attached a patch to PostGIS trunk (at rev 4206) that implements Hausdorff distance calculation using the GEOS C API provided by this patch :
ST_HausdorffDistance(geometry, geometry) and its variant with segment densification ST_HausdorffDistance(geometry, geometry, float)
Documentation (from JTS) and unit test are included.
As the GEOS patch has still not been commited, you'll have to patch and recompile geos to test it. The GEOS version test in postgis.sql.in.c are made on GEOS 31 so as to be able to test. It should be changed to the GEOS version patch #264 will be commited to.
This is my first patch for PostGIS, please be indulgent :) I'll be waiting for a review to fix or improve the patch so that it can be commited.