Hello,
yesterday I realized problem (A, B, C) with the function
tools>create>create Thiessen Polygons
First of all:
- I found this behavior in the nightly builds from 5th and 9th Sept
- Let me tell that first I checked that no points with identical
coordinates exists.
- I got the same effects under Linux (ubuntu) and Windos XP
- I could send screenshots or a sample layer if it is helpful to
reproduce it.
A) Working with small point layers (about 20 to 30 points):
Uncorrect Thiessen polygons were created but with a error message in the
status line like this: "Several points were found in the polygon:2"
B) Working with larger point layers (about 100 or several 100 points):
No Thiessen polygons were created but this error message appears:
Topology Exception
com.vividsolutions.jts.geom.TopologyException: found non-noded
intersection between LINESTRING ( 31220.85990660507 5798500.459306829,
31220.85990660591 5798500.459306829 ) and LINESTRING (
31220.859906605445 5798500.459306829, 31220.782436130103
5798500.42323841 ) [ (31220.859906605445, 5798500.459306829, NaN) ]
at
com.vividsolutions.jts.noding.FastNodingValidator.checkValid(FastNodingValidator.java:109)
at
com.vividsolutions.jts.geomgraph.EdgeNodingValidator.checkValid(EdgeNodingValidator.java:94)
at
com.vividsolutions.jts.geomgraph.EdgeNodingValidator.checkValid(EdgeNodingValidator.java:59)
at
com.vividsolutions.jts.operation.overlay.OverlayOp.computeOverlay(OverlayOp.java:170)
at
com.vividsolutions.jts.operation.overlay.OverlayOp.getResultGeometry(OverlayOp.java:127)
at
com.vividsolutions.jts.operation.overlay.OverlayOp.overlayOp(OverlayOp.java:66)
at
com.vividsolutions.jts.operation.overlay.snap.SnapOverlayOp.getResultGeometry(SnapOverlayOp.java:68)
at
com.vividsolutions.jts.operation.overlay.snap.SnapOverlayOp.overlayOp(SnapOverlayOp.java:25)
at
com.vividsolutions.jts.operation.overlay.snap.SnapIfNeededOverlayOp.getResultGeometry(SnapIfNeededOverlayOp.java:76)
at
com.vividsolutions.jts.operation.overlay.snap.SnapIfNeededOverlayOp.overlayOp(SnapIfNeededOverlayOp.java:25)
at com.vividsolutions.jts.geom.Geometry.union(Geometry.java:1140)
at
org.openjump.core.graph.delauneySimplexInsert.DTriangulationForJTS.getThiessenPolys(DTriangulationForJTS.java:298)
at
org.openjump.core.ui.plugin.tools.CreateThiessenPolygonsPlugIn.createGraph(CreateThiessenPolygonsPlugIn.java:236)
at
org.openjump.core.ui.plugin.tools.CreateThiessenPolygonsPlugIn.run(CreateThiessenPolygonsPlugIn.java:184)
at
com.vividsolutions.jump.workbench.ui.task.TaskMonitorManager$TaskWrapper.run(TaskMonitorManager.java:149)
at java.lang.Thread.run(Unknown Source)
C) Delimiting the Thiessen Polygons with a border layer do not work:
It seems that the border layer (another layer with a polygon that should
delimit the Thiessen Polygons) was not considered.
But let me tell that the option to delimit the Thiessen Polygon is
really very useful!! I was really very happy to see that!
Kindly regards
Arnd
_______________________________________________
jump-users mailing list
[email protected]
http://lists.refractions.net/mailman/listinfo/jump-users