Mercurial > dive4elements > gnv-client
changeset 433:828df3ddb758
Added interpolation capabilities along z axis to XYColumns.
gnv-artifacts/trunk@481 c6561f87-3c4e-4783-a992-168aeb5c3f6f
| author | Sascha L. Teichmann <sascha.teichmann@intevation.de> |
|---|---|
| date | Wed, 23 Dec 2009 12:20:25 +0000 |
| parents | 6a70e8883307 |
| children | 0eed5749fd63 |
| files | gnv-artifacts/ChangeLog gnv-artifacts/src/main/java/de/intevation/gnv/math/AttributedXYColumns.java gnv-artifacts/src/main/java/de/intevation/gnv/math/ConstantFunction.java gnv-artifacts/src/main/java/de/intevation/gnv/math/HeightValue.java gnv-artifacts/src/main/java/de/intevation/gnv/math/LinearFunction.java gnv-artifacts/src/main/java/de/intevation/gnv/math/XYColumn.java gnv-artifacts/src/main/java/de/intevation/gnv/math/XYDepth.java |
| diffstat | 7 files changed, 209 insertions(+), 10 deletions(-) [+] |
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--- a/gnv-artifacts/ChangeLog Wed Dec 23 09:45:40 2009 +0000 +++ b/gnv-artifacts/ChangeLog Wed Dec 23 12:20:25 2009 +0000 @@ -1,7 +1,43 @@ +2009-12-23 Sascha L. Teichmann <sascha.teichmann@intevation.de> + + * src/main/java/de/intevation/gnv/math/XYColumn.java: Added a method + prepare() which generates an continues interpolator for the + given z values. if only one value is given a constant function + is assumed. If the larger z-value is below zero the + next lower value is supplemented at zero. Symmetrically + if the lowest z-value is above the depth at the given point + the lowest value is repeated at depth. This should guarantee + that the gradient is vansihing towards the surface and the + bottom of the ocean. + + If after the supplementation there are less than three points + a linear interpolation is performed. If there are more than three + points a higher degree interpolation is used instead. This defaults + to a cubic spline interpolation. Overwrite the getInterpolator() + function to replace this behavior. + + * src/main/java/de/intevation/gnv/math/ConstantFunction.java: New. + Constant function used in interpolation. + + * src/main/java/de/intevation/gnv/math/LinearFunction.java: Added + an inner class Univariate which fits into the interpolation + framework. + + * src/main/java/de/intevation/gnv/math/HeightValue.java: Sort + z-Values in descending order because we are below zero. + + * src/main/java/de/intevation/gnv/math/XYDepth.java: New. Interface + to figure out the depth (negative values below surface) for + a given coordinate. TODO: Implement this by query the DEM grid + of the ocean. + + * src/main/java/de/intevation/gnv/math/AttributedXYColumns.java: Added + authors. + 2009-12-23 Sascha L. Teichmann <sascha.teichmann@intevation.de> * src/main/java/de/intevation/gnv/state/profile/verticalcrosssection/VerticalCrossSectionOutputState.java: - When preprocessing database data only dissamble WKT points if we + When preprocessing database data only dissemble WKT points if we have to. Read z values as double value now. Commented out CSV export because it takes the database data
--- a/gnv-artifacts/src/main/java/de/intevation/gnv/math/AttributedXYColumns.java Wed Dec 23 09:45:40 2009 +0000 +++ b/gnv-artifacts/src/main/java/de/intevation/gnv/math/AttributedXYColumns.java Wed Dec 23 12:20:25 2009 +0000 @@ -6,6 +6,10 @@ import java.io.Serializable; +/** + * @author Ingo Weinzierl + * @author Sascha L. Teichmann + */ public class AttributedXYColumns implements Serializable {
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gnv-artifacts/src/main/java/de/intevation/gnv/math/ConstantFunction.java Wed Dec 23 12:20:25 2009 +0000 @@ -0,0 +1,24 @@ +package de.intevation.gnv.math; + +import org.apache.commons.math.analysis.UnivariateRealFunction; + +/** + * @author Sascha L. Teichmann <sascha.teichmann@intevation.de> + */ +public class ConstantFunction +implements UnivariateRealFunction +{ + protected double value; + + public ConstantFunction() { + } + + public ConstantFunction(double value) { + this.value = value; + } + + public double value(double x) { + return value; + } +} +// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8:
--- a/gnv-artifacts/src/main/java/de/intevation/gnv/math/HeightValue.java Wed Dec 23 09:45:40 2009 +0000 +++ b/gnv-artifacts/src/main/java/de/intevation/gnv/math/HeightValue.java Wed Dec 23 12:20:25 2009 +0000 @@ -2,16 +2,28 @@ import java.io.Serializable; +import java.util.Comparator; + /** * @author Ingo Weinzierl <ingo.weinzierl@intevation.de> + * @author Sascha L. Teichmann <sascha.teichmann@intevation.de> */ public class HeightValue implements Serializable { - private double z; - private double v; - private int k; + public static final Comparator INV_Z_COMPARATOR = new Comparator() { + public int compare(Object a, Object b) { + HeightValue ha = (HeightValue)a; + HeightValue hb = (HeightValue)b; + if (ha.z > hb.z) return -1; + if (ha.z < hb.z) return +1; + return 0; + } + }; + public double z; + public double v; + public int k; public HeightValue(double z, double v, int k) { this.z = z; @@ -19,18 +31,16 @@ this.k = k; } - public double getZ() { return z; } - public double getV() { return v; } - public double getK() { return k; } } +// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8:
--- a/gnv-artifacts/src/main/java/de/intevation/gnv/math/LinearFunction.java Wed Dec 23 09:45:40 2009 +0000 +++ b/gnv-artifacts/src/main/java/de/intevation/gnv/math/LinearFunction.java Wed Dec 23 12:20:25 2009 +0000 @@ -4,6 +4,8 @@ import org.apache.commons.math.FunctionEvaluationException; +import org.apache.commons.math.analysis.UnivariateRealFunction; + /** * @author Sascha L. Teichmann */ @@ -12,6 +14,31 @@ { public static final LinearFunction INSTANCE = new LinearFunction(); + public static class Univariate + implements UnivariateRealFunction + { + protected double m; + protected double b; + + public Univariate() { + } + + public Univariate(double x1, double y1, double x2, double y2) { + if (y1 == y2) { + m = 0d; + b = (x1 + x2)*0.5d; + } + else { + m = (x1 - x2)/(y1 - y2); + b = y1 - m*x1; + } + } + + public double value(double x) { + return m*x + b; + } + } // class Univariate + public LinearFunction() { }
--- a/gnv-artifacts/src/main/java/de/intevation/gnv/math/XYColumn.java Wed Dec 23 09:45:40 2009 +0000 +++ b/gnv-artifacts/src/main/java/de/intevation/gnv/math/XYColumn.java Wed Dec 23 12:20:25 2009 +0000 @@ -2,6 +2,19 @@ import java.util.ArrayList; import java.util.List; +import java.util.Collections; + +import org.apache.commons.math.analysis.interpolation.SplineInterpolator; +import org.apache.commons.math.analysis.interpolation.UnivariateRealInterpolator; + +import org.apache.commons.math.analysis.polynomials.PolynomialSplineFunction; + +import org.apache.commons.math.analysis.UnivariateRealFunction; + +import org.apache.commons.math.MathException; +import org.apache.commons.math.FunctionEvaluationException; + +import org.apache.log4j.Logger; /** * @author Ingo Weinzierl <ingo.weinzierl@intevation.de> @@ -9,25 +22,98 @@ */ public class XYColumn extends Point2d +implements UnivariateRealFunction { + private static Logger log = Logger.getLogger(Interpolation2D.class); + protected List<HeightValue> values; + protected transient UnivariateRealFunction curve; + public XYColumn() { + values = new ArrayList<HeightValue>(); } public XYColumn(double x, double y, int i, int j) { super(x, y, i, j); + values = new ArrayList<HeightValue>(); } public void add(HeightValue value) { - if (values == null) { - values = new ArrayList<HeightValue>(); - } values.add(value); } public List<HeightValue> getValues() { return values; } + + public double value(double depth) { + try { + if (curve != null) { + return curve.value(depth); + } + } + catch (FunctionEvaluationException fee) { + log.error("evaluation failed", fee); + } + + return Double.NaN; + } + + public void prepare(XYDepth xyDepth) { + int N = values.size(); + if (curve == null && N > 0) { + if (N == 1) { + // only one value -> constant function + curve = new ConstantFunction(values.get(0).v); + } + else { // more than on value + double depth = xyDepth.depth(this); + Collections.sort(values, HeightValue.INV_Z_COMPARATOR); + + // if there is no value at 0 repeat first value + HeightValue first = values.get(0); + if (first.z < 0d) { + values.add(0, new HeightValue(0d, first.z, first.k-1)); + } + + // if there is no value at depth repeat last value + HeightValue last = values.get(N-1); + if (last.z > depth) { + values.add(new HeightValue(depth, last.z, last.k+1)); + } + N = values.size(); + if (N < 3) { // interpolate linear + first = values.get(0); + last = values.get(N-1); + curve = new LinearFunction.Univariate( + first.z, first.v, + last.z, last.v); + } + else { // higher degree interpolation + double [] z = new double[N]; + double [] v = new double[N]; + for (int i = 0; i < N; ++i) { + HeightValue h = values.get(i); + z[i] = h.z; + v[i] = h.v; + } + try { + curve = getInterpolator().interpolate(z, v); + } + catch (MathException me) { + log.error("interpolation failed", me); + } + } + } + } + else { + log.error("no points for interpolation"); + } + } + + protected UnivariateRealInterpolator getInterpolator() { + return new SplineInterpolator(); + } } // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8:
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gnv-artifacts/src/main/java/de/intevation/gnv/math/XYDepth.java Wed Dec 23 12:20:25 2009 +0000 @@ -0,0 +1,12 @@ +package de.intevation.gnv.math; + +import com.vividsolutions.jts.geom.Coordinate; + +/** + * @author Sascha L. Teichmann + */ +public interface XYDepth +{ + double depth(Coordinate coordinate); +} +// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8: