Arnd,

  Just one thought: can you verify that your field measurement layer is
coming in as Point and not MultiPoint.

Larry

On Thu, Sep 18, 2008 at 10:46 AM, Arnd Kielhorn <[EMAIL PROTECTED]> wrote:

> Hello Stefan,
>
> today I tested again with the Thiessen polygon tool. I used a new layer
> with "fresh" drawn points (191 points without attributes), a point layer
> from field measurement (with several attributes) and got different results:
>
> - "fresh" drawn points: correct Thiessen polygon
> - point layer from field measurements (imported as PIROL-CSV or JML): no
> Thiessen polygon but the described long error message (see below: B), if
> the there are too many points
> AND
> incorrect Thiessen polygons (see attachment), if there are not so many
> points (I filtered points under 10 meters).
>
> So, it seems that there special requirements to the point layer?
>
> I have no idea of an explanation, I only noticed this behaviour...
>
> Kindly regards
> Arnd
>
> Stefan Steiniger schrieb:
> > Hei Arnd,
> >
> > probably not a very useful answer
> > a) problem A+B seem to be configuration problem. Unfortuanetly I am
> > not able to solve them , as I did not wrote the triangulation/voronoi
> > algorithm. Not sure what I can do here - except to find a replacement
> > for the current algorithm.
> >
> > on B) would it be sufficient to deliver just the thiessen lines back
> > and the to try polygonization by hand?
> >
> > b) i need to check problem C, but I am not sure if there is a
> > misunderstanding. The background-border-layer is only used to
> > determine the dimensions of the final output (i.e. to avoid having a
> > too small output). Not sure if this is what you thought?
> >
> > btw. I am not sure when I can have a look at this things as I am
> > traveling till beginning of October (I am in Freiburg - GER - right now)
> >
> > stefan
> >
> > Arnd Kielhorn schrieb:
> >> 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
> >>
> >>
> > _______________________________________________
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> >
>
>
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