From f276491efb27d8edbf04729ea56cb66736cc5fb7 Mon Sep 17 00:00:00 2001 From: jic13003 Date: Fri, 4 Dec 2015 19:53:16 -0500 Subject: [PATCH 1/3] made it start a graph, need to work on integrator --- .../ThreeBodyExample/ThreeBodyAPL.java | 26 ++++++- .../ThreeBodyExample/ThreeBodyExample.java | 71 +++++++++++++++---- 2 files changed, 81 insertions(+), 16 deletions(-) diff --git a/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java b/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java index 41a565c..6c642dc 100644 --- a/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java +++ b/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java @@ -1,12 +1,19 @@ package jat.examples.ThreeBodyExample; +import java.util.ArrayList; + import org.apache.commons.math3.ode.FirstOrderDifferentialEquations; +import org.apache.commons.math3.ode.sampling.StepHandler; +import org.apache.commons.math3.ode.sampling.StepInterpolator; import jat.coreNOSA.cm.ThreeBody; import jat.coreNOSA.math.MatrixVector.data.VectorN; public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEquations{ - + public ArrayList time = new ArrayList(); + public ArrayList xsol = new ArrayList(); + public ArrayList ysol = new ArrayList(); + public ArrayList zsol = new ArrayList(); public ThreeBodyAPL(double G, double m1, double m2, double m3) { super(G, m1, m2, m3); } @@ -20,7 +27,7 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu @Override public int getDimension() { // returns a dimension of 6 - return 6; + return 18; } public double[] randv() { double[] randv = new double[18]; @@ -44,4 +51,19 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu randv[17] = 8.0; return randv; } + + public StepHandler stepHandler = new StepHandler() { + public void init(double t0, double[] y0, double t) { + } + + public void handleStep(StepInterpolator interpolator, boolean isLast) { + double t = interpolator.getCurrentTime(); + double[] y = interpolator.getInterpolatedState(); + // System.out.println(t + " " + y[0] + " " + y[1]+ " " + y[2]); + time.add(t); + xsol.add(y[0]); + ysol.add(y[1]); + zsol.add(y[2]); + } + }; } diff --git a/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java b/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java index ecdf71b..c84205f 100644 --- a/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java +++ b/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java @@ -20,23 +20,24 @@ import org.apache.commons.math3.ode.FirstOrderIntegrator; import org.apache.commons.math3.ode.nonstiff.DormandPrince853Integrator; public class ThreeBodyExample { + public ThreeBodyExample() { } - + public static void main(String[] args) { // Class that solves a three body problem and plots it ThreeBodyExample x = new ThreeBodyExample(); - + //initialize variables double totalEnergy = 0; // set the final time = one orbit period - double tf = 2.0; - + double tf = 7.0; + // create a ThreeBody orbit using three masses and gravitational con ThreeBodyAPL sat = new ThreeBodyAPL(10, 0.3, 1.0, 2.0); //initialize VectorN elements double[] y = sat.randv(); - + ArrayRealVector v = new ArrayRealVector(y); DecimalFormat df2 = new DecimalFormat("#,###,###,##0.00"); @@ -45,27 +46,69 @@ public class ThreeBodyExample { // find out the derivs of the problem double[] derivs = sat.derivs(tf, y); - + // set the initial time to zero double t0 = 0.0; // obtain center of mass VectorN cm = sat.center_of_mass(y); - + // obtain current energy totalEnergy = sat.Energy(y); - + // propagate the orbit - //FirstOrderIntegrator dp853 = new DormandPrince853Integrator(1.0e-8, 100.0, 1.0e-10, 1.0e-10); - //dp853.addStepHandler(sat.stepHandler); - // double[] y = new double[] { 7000.0, 0, 0, .0, 8, 0 }; // initial - // state - //test outputs + FirstOrderIntegrator dp853 = new DormandPrince853Integrator(1.0e-8, 100.0, 1.0e-10, 1.0e-10); + dp853.addStepHandler(sat.stepHandler); + // double[] y = new double[] { 7000.0, 0, 0, .0, 8, 0 }; // initial + // state + + dp853.integrate(sat, 0.0, y, 8000, y); // now y contains final state at + // tf + + Double[] objArray = sat.time.toArray(new Double[sat.time.size()]); + double[] timeArray = ArrayUtils.toPrimitive(objArray); + double[] xsolArray = ArrayUtils.toPrimitive(sat.xsol.toArray(new Double[sat.time.size()])); + double[] ysolArray = ArrayUtils.toPrimitive(sat.ysol.toArray(new Double[sat.time.size()])); + + double[][] XY = new double[timeArray.length][2]; + + // int a=0; + // System.arraycopy(timeArray,0,XY[a],0,timeArray.length); + // System.arraycopy(ysolArray,0,XY[1],0,ysolArray.length); + + for (int i = 0; i < timeArray.length; i++) { + XY[i][0] = xsolArray[i]; + XY[i][1] = ysolArray[i]; + } + + Plot2DPanel p = new Plot2DPanel(); + + // Plot2DPanel p = new Plot2DPanel(min, max, axesScales, axesLabels); + + ScatterPlot s = new ScatterPlot("orbit", Color.RED, XY); + // LinePlot l = new LinePlot("sin", Color.RED, XY); + // l.closed_curve = false; + // l.draw_dot = true; + p.addPlot(s); + p.setLegendOrientation(PlotPanel.SOUTH); + double plotSize = 10000.; + double[] min = { -plotSize, -plotSize }; + double[] max = { plotSize, plotSize }; + + p.setFixedBounds(min, max); + // test outputs + // output derivatives for (int i = 0; i< derivs.length; i++) { System.out.println(derivs[i]); } + + // output center of mass System.out.println(cm); + + // output total energy of the system System.out.println(totalEnergy); - } + new FrameView(p).setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); + System.out.println("end"); + } } From 47dd6e6edf7eea7f58a3ba350a8aee99f0188344 Mon Sep 17 00:00:00 2001 From: John Costa III Date: Sun, 6 Dec 2015 12:40:32 -0500 Subject: [PATCH 2/3] Stephandler methods added to ThreeBodyAPL, began trying to figure out how to integrate the derivatives. there's a few comments that I unchecked to show the outputs of energy, center of mass, and the derivatives. Also, this does return a graph, but no changes are observed in the plot, so it results in one dot. --- .../ThreeBodyExample/ThreeBodyAPL.java | 24 ++++++++++++++----- .../ThreeBodyExample/ThreeBodyExample.java | 6 ++--- 2 files changed, 21 insertions(+), 9 deletions(-) diff --git a/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java b/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java index 6c642dc..f22a529 100644 --- a/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java +++ b/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java @@ -2,10 +2,13 @@ package jat.examples.ThreeBodyExample; import java.util.ArrayList; +import org.apache.commons.math3.geometry.euclidean.threed.Vector3D; import org.apache.commons.math3.ode.FirstOrderDifferentialEquations; import org.apache.commons.math3.ode.sampling.StepHandler; import org.apache.commons.math3.ode.sampling.StepInterpolator; +import jat.coreNOSA.algorithm.integrators.Printable; +import jat.coreNOSA.cm.Constants; import jat.coreNOSA.cm.ThreeBody; import jat.coreNOSA.math.MatrixVector.data.VectorN; @@ -14,14 +17,15 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu public ArrayList xsol = new ArrayList(); public ArrayList ysol = new ArrayList(); public ArrayList zsol = new ArrayList(); + public ThreeBodyAPL(double G, double m1, double m2, double m3) { super(G, m1, m2, m3); } @Override - public void computeDerivatives(double arg0, double[] arg1, double[] arg2) { - // TODO Auto-generated method stub - + public void computeDerivatives(double t, double[] y, double[] yDot) { + // returns the derivatives of the ThreeBody problem + yDot = this.derivs(t, y); } @Override @@ -30,6 +34,13 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu return 18; } public double[] randv() { + // returns the position and velocity of the three objects + // vector r1 is x[0], x[1], x[2] + // vector v1 is x[3], x[4], x[5] + // vector r2 is x[6], x[7], x[8] + // vector v2 is x[9], x[10], x[11] + // vector r3 is x[12], x[13], x[14] + // vector v3 is x[15], x[16], x[17] double[] randv = new double[18]; randv[0] = 2.0; randv[1] = 6.0; @@ -51,7 +62,7 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu randv[17] = 8.0; return randv; } - + public StepHandler stepHandler = new StepHandler() { public void init(double t0, double[] y0, double t) { } @@ -59,11 +70,12 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu public void handleStep(StepInterpolator interpolator, boolean isLast) { double t = interpolator.getCurrentTime(); double[] y = interpolator.getInterpolatedState(); - // System.out.println(t + " " + y[0] + " " + y[1]+ " " + y[2]); + System.out.println(t + " " + y[0] + " " + y[1]+ " " + y[2]); time.add(t); xsol.add(y[0]); ysol.add(y[1]); zsol.add(y[2]); } }; -} + +} \ No newline at end of file diff --git a/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java b/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java index c84205f..e9243c8 100644 --- a/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java +++ b/src/jat/examples/ThreeBodyExample/ThreeBodyExample.java @@ -31,10 +31,10 @@ public class ThreeBodyExample { //initialize variables double totalEnergy = 0; // set the final time = one orbit period - double tf = 7.0; + double tf = 1.0; // create a ThreeBody orbit using three masses and gravitational con - ThreeBodyAPL sat = new ThreeBodyAPL(10, 0.3, 1.0, 2.0); + ThreeBodyAPL sat = new ThreeBodyAPL(9.87, 0.3, 1.0, 2.0); //initialize VectorN elements double[] y = sat.randv(); @@ -71,7 +71,7 @@ public class ThreeBodyExample { double[][] XY = new double[timeArray.length][2]; - // int a=0; + int a=0; // System.arraycopy(timeArray,0,XY[a],0,timeArray.length); // System.arraycopy(ysolArray,0,XY[1],0,ysolArray.length); From cdf88d4683ad12d02cfccf06d6688fd935c2b32d Mon Sep 17 00:00:00 2001 From: jic13003 Date: Sun, 6 Dec 2015 20:05:49 -0500 Subject: [PATCH 3/3] latest working version --- src/jat/coreNOSA/cm/ThreeBody.java | 6 +++--- src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java | 4 ++-- 2 files changed, 5 insertions(+), 5 deletions(-) diff --git a/src/jat/coreNOSA/cm/ThreeBody.java b/src/jat/coreNOSA/cm/ThreeBody.java index a9eaabd..ef46b20 100644 --- a/src/jat/coreNOSA/cm/ThreeBody.java +++ b/src/jat/coreNOSA/cm/ThreeBody.java @@ -34,9 +34,9 @@ import jat.coreNOSA.math.MatrixVector.data.VectorN; public class ThreeBody implements Derivatives //, Printable { - - private double G; // Gravitational constant - private double m1, m2, m3; // masses + protected double steps = 500.; + protected double G; // Gravitational constant + protected double m1, m2, m3; // masses /** * Method ThreeBody. diff --git a/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java b/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java index f22a529..f1d5d07 100644 --- a/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java +++ b/src/jat/examples/ThreeBodyExample/ThreeBodyAPL.java @@ -17,9 +17,10 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu public ArrayList xsol = new ArrayList(); public ArrayList ysol = new ArrayList(); public ArrayList zsol = new ArrayList(); - + protected double[] randv[]; public ThreeBodyAPL(double G, double m1, double m2, double m3) { super(G, m1, m2, m3); + this.randv(); } @Override @@ -77,5 +78,4 @@ public class ThreeBodyAPL extends ThreeBody implements FirstOrderDifferentialEqu zsol.add(y[2]); } }; - } \ No newline at end of file