The reason for the appearance of the extra vertices is that the Delaunay
algorithm surrounds the input data with a known-convex "frame", in order to
simplify the processing. These vertices are part of the frame. (See
QuadEdgeSubdivision.createFrame - which also provides methods to test
whether a Vertex is part of the frame).
Sorry for the delay in replying.
On Fri, Jun 21, 2013 at 12:05 AM, SK <[email protected]> wrote:
> Hi, this is test example -- it gives same strange results.
>
> import com.vividsolutions.jts.geom.Coordinate;
> import com.vividsolutions.jts.geom.Envelope;
> import com.vividsolutions.jts.geom.Geometry;
> import com.vividsolutions.jts.geom.MultiPoint;
> import com.vividsolutions.jts.io.WKTReader;
> import com.vividsolutions.jts.triangulate.DelaunayTriangulationBuilder;
> import com.vividsolutions.jts.triangulate.quadedge.QuadEdge;
> import com.vividsolutions.jts.triangulate.quadedge.QuadEdgeSubdivision;
> import com.vividsolutions.jts.triangulate.quadedge.Vertex;
> import java.util.ArrayList;
>
> /**
> *
> * @author karasiov
> */
> public class QuadEdgeTest {
>
> public static void main(String[] args) throws Exception{
>
> WKTReader w = new WKTReader();
> Geometry g = w.read(sinXminusSinY);
> DelaunayTriangulationBuilder builder = new DelaunayTriangulationBuilder();
>
> MultiPoint mpt = (MultiPoint)g;
> builder.setSites(mpt);
> QuadEdgeSubdivision subdiv = builder.getSubdivision();
>
> Envelope env = mpt.getEnvelopeInternal();
>
> System.out.println(env);
> ArrayList<Integer> lat = new ArrayList<Integer>();
> ArrayList<Integer> lon = new ArrayList<Integer>();
> for(int i = -6; i<7;i++ ){lat.add(i);}
> for(int i = -3; i<4;i++ ){lon.add(i);}
>
> double[][] iso = new double[lon.size()][lat.size()];
>
> for(int a=0; a<iso[0].length; a++){
> for(int o=0; o<iso.length; o++){
> double val = interpolateZ(subdiv, new
> Coordinate(lat.get(a), lon.get(o)));
> //System.out.println(val);
> }
>
> }
> }
>
> public static double interpolateZ(QuadEdgeSubdivision quadEdgeSubdivision,
> Coordinate coordinate) {
> QuadEdge edge = quadEdgeSubdivision.locate(coordinate);
> System.out.println(edge);
> return new Vertex(coordinate.x,
> coordinate.y).interpolateZValue(edge.orig(), edge.dest(),
> edge.oNext().dest());
> }
> //[[(x, y, (sin x -sin y)*10)| x <- [-6..6]] | y <- [-3..3]]
> static String sinXminusSinY = "MULTIPOINT ("
> + " (-6.0 -3.0 4.205355062587931 ),"
> + "(-5.0 -3.0 11.000442827230057 ),"
> + "(-4.0 -3.0 8.979225033677954 ),"
> + "(-3.0 -3.0 0.0 ),"
> + "(-2.0 -3.0 -7.681774187658145 ),"
> + "(-1.0 -3.0 -7.003509767480293 ),"
> + "(0.0 -3.0 1.4112000805986722 ),"
> + "(1.0 -3.0 9.825909928677637 ),"
> + "(2.0 -3.0 10.50417434885549 ),"
> + "(3.0 -3.0 2.8224001611973444 ),"
> + "(4.0 -3.0 -6.15682487248061 ),"
> + "(5.0 -3.0 -8.178042666032713 ),"
> + "(6.0 -3.0 -1.3829549013905864) ,"
> + "(-6.0 -2.0 11.887129250246076 ),"
> + "(-5.0 -2.0 18.682217014888202 ),"
> + "(-4.0 -2.0 16.6609992213361 ),"
> + "(-3.0 -2.0 7.681774187658145 ),"
> + "(-2.0 -2.0 0.0 ),"
> + "(-1.0 -2.0 0.678264420177852 ),"
> + "(0.0 -2.0 9.092974268256818 ),"
> + "(1.0 -2.0 17.50768411633578 ),"
> + "(2.0 -2.0 18.185948536513635 ),"
> + "(3.0 -2.0 10.50417434885549 ),"
> + "(4.0 -2.0 1.524949315177535 ),"
> + "(5.0 -2.0 -0.49626847837456745 ),"
> + "(6.0 -2.0 6.298819286267559) ,"
> + "(-6.0 -1.0 11.208864830068224 ),"
> + "(-5.0 -1.0 18.00395259471035 ),"
> + "(-4.0 -1.0 15.982734801158248 ),"
> + "(-3.0 -1.0 7.003509767480293 ),"
> + "(-2.0 -1.0 -0.678264420177852 ),"
> + "(-1.0 -1.0 0.0 ),"
> + "(0.0 -1.0 8.414709848078965 ),"
> + "(1.0 -1.0 16.82941969615793 ),"
> + "(2.0 -1.0 17.50768411633578 ),"
> + "(3.0 -1.0 9.825909928677637 ),"
> + "(4.0 -1.0 0.846684894999683 ),"
> + "(5.0 -1.0 -1.1745328985524195 ),"
> + "(6.0 -1.0 5.620554866089707) ,"
> + "(-6.0 0.0 2.7941549819892586 ),"
> + "(-5.0 0.0 9.589242746631385 ),"
> + "(-4.0 0.0 7.5680249530792825 ),"
> + "(-3.0 0.0 -1.4112000805986722 ),"
> + "(-2.0 0.0 -9.092974268256818 ),"
> + "(-1.0 0.0 -8.414709848078965 ),"
> + "(0.0 0.0 0.0 ),"
> + "(1.0 0.0 8.414709848078965 ),"
> + "(2.0 0.0 9.092974268256818 ),"
> + "(3.0 0.0 1.4112000805986722 ),"
> + "(4.0 0.0 -7.5680249530792825 ),"
> + "(5.0 0.0 -9.589242746631385 ),"
> + "(6.0 0.0 -2.7941549819892586) ,"
> + "(-6.0 1.0 -5.620554866089707 ),"
> + "(-5.0 1.0 1.1745328985524195 ),"
> + "(-4.0 1.0 -0.846684894999683 ),"
> + "(-3.0 1.0 -9.825909928677637 ),"
> + "(-2.0 1.0 -17.50768411633578 ),"
> + "(-1.0 1.0 -16.82941969615793 ),"
> + "(0.0 1.0 -8.414709848078965 ),"
> + "(1.0 1.0 0.0 ),"
> + "(2.0 1.0 0.678264420177852 ),"
> + "(3.0 1.0 -7.003509767480293 ),"
> + "(4.0 1.0 -15.982734801158248 ),"
> + "(5.0 1.0 -18.00395259471035 ),"
> + "(6.0 1.0 -11.208864830068224) ,"
> + "(-6.0 2.0 -6.298819286267559 ),"
> + "(-5.0 2.0 0.49626847837456745 ),"
> + "(-4.0 2.0 -1.524949315177535 ),"
> + "(-3.0 2.0 -10.50417434885549 ),"
> + "(-2.0 2.0 -18.185948536513635 ),"
> + "(-1.0 2.0 -17.50768411633578 ),"
> + "(0.0 2.0 -9.092974268256818 ),"
> + "(1.0 2.0 -0.678264420177852 ),"
> + "(2.0 2.0 0.0 ),"
> + "(3.0 2.0 -7.681774187658145 ),"
> + "(4.0 2.0 -16.6609992213361 ),"
> + "(5.0 2.0 -18.682217014888202 ),"
> + "(6.0 2.0 -11.887129250246076) ,"
> + "(-6.0 3.0 1.3829549013905864 ),"
> + "(-5.0 3.0 8.178042666032713 ),"
> + "(-4.0 3.0 6.15682487248061 ),"
> + "(-3.0 3.0 -2.8224001611973444 ),"
> + "(-2.0 3.0 -10.50417434885549 ),"
> + "(-1.0 3.0 -9.825909928677637 ),"
> + "(0.0 3.0 -1.4112000805986722 ),"
> + "(1.0 3.0 7.003509767480293 ),"
> + "(2.0 3.0 7.681774187658145 ),"
> + "(3.0 3.0 0.0 ),"
> + "(4.0 3.0 -8.979225033677954 ),"
> + "(5.0 3.0 -11.000442827230057 ),"
> + "(6.0 3.0 -4.205355062587931))";
> }
>
>
>
> On Fri, Jun 21, 2013 at 2:27 AM, Martin Davis <[email protected]> wrote:
>
>> If you can provide runnable Java test code that will make it easier to
>> help.
>>
>>
>> On Thu, Jun 20, 2013 at 3:23 PM, SK <[email protected]> wrote:
>>
>>> Hi,
>>> I have simple test data
>>> //[[(x, y, (sin x -sin y)*10)| x <- [-6..6]] | y <- [-3..3]]
>>> static String sinXminusSinY = "MULTIPOINT ("
>>> + " (-6.0 -3.0 4.205355062587931 ),"
>>> + "(-5.0 -3.0 11.000442827230057 ),"
>>> + "(-4.0 -3.0 8.979225033677954 ),"
>>> + "(-3.0 -3.0 0.0 ),"
>>> + "(-2.0 -3.0 -7.681774187658145 ),"
>>> + "(-1.0 -3.0 -7.003509767480293 ),"
>>> + "(0.0 -3.0 1.4112000805986722 ),"
>>> + "(1.0 -3.0 9.825909928677637 ),"
>>> + "(2.0 -3.0 10.50417434885549 ),"
>>> + "(3.0 -3.0 2.8224001611973444 ),"
>>> + "(4.0 -3.0 -6.15682487248061 ),"
>>> + "(5.0 -3.0 -8.178042666032713 ),"
>>> + "(6.0 -3.0 -1.3829549013905864) ," etc
>>>
>>> Next I triangulate this and get subdivision
>>>
>>> QuadEdgeSubdivision subdiv = builder.getSubdivision();
>>>
>>> Now I need to fill an array [-6, 6]x[-3, 3]
>>>
>>> and I try to interpolate my data in cycle
>>> double val = interpolateZ(subdiv, new Coordinate(myX, myY));
>>>
>>> //(I found this on Stackoverflow)
>>> public static double interpolateZ(QuadEdgeSubdivision
>>> quadEdgeSubdivision, Coordinate coordinate) {
>>> QuadEdge edge = quadEdgeSubdivision.locate(coordinate);
>>> System.out.println(edge.toString());///!!!See below
>>> return new Vertex(coordinate.x,
>>> coordinate.y).interpolateZValue(edge.orig(), edge.dest(),
>>> edge.oNext().dest());
>>> }
>>>
>>> But I have a NaN processing column of my sample data.
>>> When I print edge I get strange result. I have no any 126, 123 in my
>>> programm.
>>> LINESTRING ( -126.0 -123.0, -6.0 -3.0 )
>>> LINESTRING ( -126.0 -123.0, -6.0 -2.0 )
>>> LINESTRING ( -126.0 -123.0, -6.0 -1.0 )
>>> LINESTRING ( -126.0 -123.0, -6.0 0.0 )
>>> LINESTRING ( -126.0 -123.0, -6.0 1.0 )
>>> LINESTRING ( -126.0 -123.0, -6.0 2.0 )
>>> LINESTRING ( -126.0 -123.0, -6.0 3.0 )
>>>
>>> Is it normal or I did something wrong?
>>> Thank you
>>> CK
>>>
>>>
>>> ------------------------------------------------------------------------------
>>> This SF.net email is sponsored by Windows:
>>>
>>> Build for Windows Store.
>>>
>>> http://p.sf.net/sfu/windows-dev2dev
>>> _______________________________________________
>>> Jts-topo-suite-user mailing list
>>> [email protected]
>>> https://lists.sourceforge.net/lists/listinfo/jts-topo-suite-user
>>>
>>>
>>
>>
>> ------------------------------------------------------------------------------
>> This SF.net email is sponsored by Windows:
>>
>> Build for Windows Store.
>>
>> http://p.sf.net/sfu/windows-dev2dev
>> _______________________________________________
>> Jts-topo-suite-user mailing list
>> [email protected]
>> https://lists.sourceforge.net/lists/listinfo/jts-topo-suite-user
>>
>>
>
------------------------------------------------------------------------------
This SF.net email is sponsored by Windows:
Build for Windows Store.
http://p.sf.net/sfu/windows-dev2dev
_______________________________________________
Jts-topo-suite-user mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/jts-topo-suite-user
