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Further improvements. 

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/math/trunk@1539775 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
Thomas Neidhart 2013-11-07 19:36:38 +00:00
parent 346a41fc6b
commit 6b18e3897a
2 changed files with 10 additions and 20 deletions
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15
src/userguide/java/org/apache/commons/math3/userguide/filter/CannonballExample.java
View File

@ -124,15 +124,6 @@ public class CannonballExample {
public static void cannonballTest(Chart chart) {
// Let's go over the physics behind the cannon shot, just to make sure it's
// correct:
// sin(45)*100 = 70.710 and cos(45)*100 = 70.710
// vf = vo + at
// 0 = 70.710 + (-9.81)t
// t = 70.710/9.81 = 7.208 seconds for half
// 14.416 seconds for full journey
// distance = 70.710 m/s * 14.416 sec = 1019.36796 m
// time interval for each iteration
final double dt = 0.1;
// the number of iterations to run
@ -166,7 +157,7 @@ public class CannonballExample {
final RealVector controlVector =
MatrixUtils.createRealVector(new double[] { 0, 0, 0.5 * -9.81 * dt * dt, -9.81 * dt } );
// The control matrix B only expects y and vy, see control vector
// The control matrix B only update y and vy, see control vector
final RealMatrix B = MatrixUtils.createRealMatrix(new double[][] {
{ 0, 0, 0, 0 },
{ 0, 0, 0, 0 },
@ -178,8 +169,8 @@ public class CannonballExample {
//
// x(n+1) = x(n) + vx(n)
// vx(n+1) = vx(n)
// y(n+1) = y(n) + vy(n) - 0.5*9.81*dt^2
// vy(n+1) = vy(n) + -9.81*dt
// y(n+1) = y(n) + vy(n) - 0.5 * 9.81 * dt^2
// vy(n+1) = vy(n) + -9.81 * dt
//
// Which, if you recall, are the equations of motion for a parabola.

15
src/userguide/java/org/apache/commons/math3/userguide/filter/ConstantVoltageExample.java
View File

@ -90,7 +90,7 @@ public class ConstantVoltageExample {
public static void constantVoltageTest(Chart chart1, Chart chart2) {
final double voltage = 1.25d;
final double measurementNoise = 0.1d; // measurement noise (V) - std dev
final double measurementNoise = 0.2d; // measurement noise (V) - std dev
final double processNoise = 1e-5d;
final VoltMeter voltMeter = new VoltMeter(voltage, processNoise, measurementNoise, 2);
@ -111,7 +111,7 @@ public class ConstantVoltageExample {
final RealMatrix Q = new Array2DRowRealMatrix(new double[] { processNoise * processNoise });
// the initial error covariance -> assume a large error at the beginning
final RealMatrix P0 = new Array2DRowRealMatrix(new double[] { 1 });
final RealMatrix P0 = new Array2DRowRealMatrix(new double[] { 0.1 });
// the measurement covariance matrix -> put the "real" variance
RealMatrix R = new Array2DRowRealMatrix(new double[] { measurementNoise * measurementNoise });
@ -127,7 +127,7 @@ public class ConstantVoltageExample {
final List<Number> covSeries = new ArrayList<Number>();
for (int i = 0; i < 200; i++) {
for (int i = 0; i < 300; i++) {
xAxis.add(i);
voltMeter.step();
@ -138,12 +138,11 @@ public class ConstantVoltageExample {
final double measuredVoltage = voltMeter.getMeasuredVoltage();
measuredVoltageSeries.add(measuredVoltage);
kalmanVoltageSeries.add(filter.getStateEstimation()[0]);
covSeries.add(filter.getErrorCovariance()[0][0]);
filter.predict();
filter.correct(new double[] { measuredVoltage });
kalmanVoltageSeries.add(filter.getStateEstimation()[0]);
covSeries.add(filter.getErrorCovariance()[0][0]);
}
chart1.setYAxisTitle("Voltage");
@ -199,7 +198,7 @@ public class ConstantVoltageExample {
JComponent container = new JPanel();
container.setLayout(new BoxLayout(container, BoxLayout.LINE_AXIS));
Chart chart1 = createChart("Filter", 550, 450, LegendPosition.InsideNE, true);
Chart chart1 = createChart("Voltage", 550, 450, LegendPosition.InsideNE, true);
Chart chart2 = createChart("Error Covariance", 450, 450, LegendPosition.InsideNE, false);
constantVoltageTest(chart1, chart2);