Re: scatter plot and mark each data point with a shape


I have composed a simple code (see below) to do 2D scatter, but I see no data
points on the screen marked by the defined shape square.  Can anyone tell me
what I did wrong in the folowing code?

Thanks a lot. /Helen
------------- code follows -------------

import visad.*;
import visad.java2d.DisplayImplJ2D;
import java.rmi.RemoteException;
import java.awt.*;
import javax.swing.*;

public class ScatterPlot2D {

  private RealType time, height, mark, scale, index;
  private RealTupleType t_h_tuple;
  private FunctionType func_i_tuple;
  private Set index_set;
  private FlatField vals_ff;

  private DataReferenceImpl data_ref;
  private DisplayImpl display;
  private ScalarMap timeMap, heightMap, markMap, scaleMap;

    /** Creates a new instance of ScatterPlot2D */
    public ScatterPlot2D() throws RemoteException, VisADException {

        time = RealType.getRealType("time");
        height = RealType.getRealType("height");
        mark = RealType.getRealType("mark");
        scale = RealType.getRealType("scale");

        t_h_tuple = new RealTupleType( time, height, mark, scale);

        index = RealType.getRealType("index");

        func_i_tuple = new FunctionType( index, t_h_tuple);

        index_set = new Integer1DSet(index, 5);

        display = new DisplayImplJ2D("display1");

        GraphicsModeControl dispGMC = (GraphicsModeControl)

        timeMap = new ScalarMap( time, Display.XAxis );
        heightMap = new ScalarMap( height, Display.YAxis );
        markMap = new ScalarMap(mark, Display.Shape);
        scaleMap = new ScalarMap(scale, Display.ShapeScale);

        timeMap.setRange( -4.0, 4.0);
        heightMap.setRange( -10.0, 50.0);
        scaleMap.setRange(0.01, 10.0);

        // Add maps to display

        display.addMap( timeMap );
        display.addMap( heightMap );

        display.addMap( markMap );
        display.addMap( scaleMap );

        VisADQuadArray square = new VisADQuadArray();
        square.coordinates = new float[]
        {0.1f,  0.1f, 0.0f,     0.1f, -0.1f, 0.0f,
        -0.1f, -0.1f, 0.0f,    -0.1f,  0.1f, 0.0f};
        square.vertexCount = square.coordinates.length / 3;

        float[][] counts = {{0.0f,1.0f,2.0f, 3.0f,4.0f}};
        Gridded1DSet count_set = new Gridded1DSet(mark, counts,

        VisADGeometryArray[] shapes = {square,square,square,square,square};
        ShapeControl shape_control = (ShapeControl) markMap.getControl();

        float[][] point_vals = new float[][]{{-3.0f, -1.5f, 0.0f, 1.5f,
              {0.0f, 33.75f, 45.0f, 33.75f, 0.0f,},
                                             {0.0f,  1.0f,  2.0f,  3.0f,
                                             {1.0f,  2.0f,  3.0f,  4.0f,

        vals_ff = new FlatField( func_i_tuple, index_set);

        vals_ff.setSamples( point_vals );

        // Create a data reference and set the FlatField as our data

        data_ref = new DataReferenceImpl("data_ref");

        data_ref.setData( vals_ff );

        display.addReference( data_ref);

       // Create application window, put display into it

    JFrame jframe = new JFrame("VisAD Tutorial example 2_03");

    // Set window size and make it visible

    jframe.setSize(300, 300);


     * @param args the command line arguments
    public static void main(String[] args) throws RemoteException,
VisADException {
        new ScatterPlot2D();


Bill Hibbard wrote:

> Hi Helen,
> > I like to draw a 2D scatter plot. Following the example P2_04 in
> > tutorial, it is easy to create a 2D scatter plot with certain size
> > points. But how can I change those points to the  shapes, such as filled
> > triangle or dimond, with changable ShapeScale?
> P2_04 has a Field with MathType ( index -> (time, height) ) and
> ScalarMaps time -> XAxis and height -> YAxis. To use Shape you
> can add ScalarMaps of time or height to Shape and ShapeScale, or
> better yet use shapes to add some new information. For this,
> expand your Field to include other variables, such as:
>   ( index -> (time, height, u, v) )
> and Display with ScalarMaps:
>   time -> XAxis
>   height -> YAxis
>   u -> Shape
>   v -> ShapeScale
> See and in visad/examples for examples
> of how to use Shape and ShapeScale.
> Good luck,
> Bill