/**
* Copyright (C) 2013 - present by OpenGamma Inc. and the OpenGamma group of companies
*
* Please see distribution for license.
*/
package com.opengamma.analytics.math.interpolation;
import static com.opengamma.analytics.math.matrix.MatrixAlgebraFactory.OG_ALGEBRA;
import static org.testng.Assert.assertEquals;
import java.util.Random;
import org.testng.annotations.Test;
import com.opengamma.analytics.math.function.PiecewisePolynomialFunction1D;
import com.opengamma.analytics.math.function.PiecewisePolynomialFunction2D;
import com.opengamma.analytics.math.matrix.DoubleMatrix2D;
import com.opengamma.util.test.TestGroup;
/**
* Test.
*/
@Test(groups = TestGroup.UNIT)
public class BicubicSplineInterpolatorTest {
private static final double EPS = 1e-12;
private static final double INF = 1. / 0.;
/**
*
*/
@Test
public void linearTest() {
double[] x0Values = new double[] {1., 2., 3., 4. };
double[] x1Values = new double[] {-1., 0., 1., 2., 3. };
final int n0Data = x0Values.length;
final int n1Data = x1Values.length;
double[][] yValues = new double[n0Data][n1Data];
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
yValues[i][j] = (x0Values[i] + 2.) * (x1Values[j] + 5.);
}
}
// System.out.println(new DoubleMatrix2D(yValues));
CubicSplineInterpolator method = new CubicSplineInterpolator();
PiecewisePolynomialInterpolator2D interp = new BicubicSplineInterpolator(new CubicSplineInterpolator[] {method, method });
PiecewisePolynomialResult2D result = interp.interpolate(x0Values, x1Values, yValues);
final int n0IntExp = n0Data - 1;
final int n1IntExp = n1Data - 1;
final int orderExp = 4;
DoubleMatrix2D[][] coefsExp = new DoubleMatrix2D[n0Data - 1][n1Data - 1];
for (int i = 0; i < n0Data - 1; ++i) {
for (int j = 0; j < n1Data - 1; ++j) {
coefsExp[i][j] = new DoubleMatrix2D(new double[][] { {0., 0., 0., 0., }, {0., 0., 0., 0., }, {0., 0., 1., (5. + x1Values[j]) },
{0., 0., (2. + x0Values[i]), (2. + x0Values[i]) * (5. + x1Values[j]) } });
}
}
assertEquals(result.getNumberOfIntervals()[0], n0IntExp);
assertEquals(result.getNumberOfIntervals()[1], n1IntExp);
assertEquals(result.getOrder()[0], orderExp);
assertEquals(result.getOrder()[1], orderExp);
final int n0Keys = 51;
final int n1Keys = 61;
double[] x0Keys = new double[n0Keys];
double[] x1Keys = new double[n1Keys];
for (int i = 0; i < n0Keys; ++i) {
x0Keys[i] = 0. + 5. * i / (n0Keys - 1);
}
for (int i = 0; i < n1Keys; ++i) {
x1Keys[i] = -2. + 6. * i / (n1Keys - 1);
}
// PiecewisePolynomialFunction2D func = new PiecewisePolynomialFunction2D();
// final double[][] values = func.evaluate(result, x0Keys, x1Keys).getData();
for (int i = 0; i < n0Data; ++i) {
final double ref = Math.abs(x0Values[i]) == 0. ? 1. : Math.abs(x0Values[i]);
assertEquals(result.getKnots0().getData()[i], x0Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(0).getData()[i], x0Values[i], ref * EPS);
}
for (int i = 0; i < n1Data; ++i) {
final double ref = Math.abs(x1Values[i]) == 0. ? 1. : Math.abs(x1Values[i]);
assertEquals(result.getKnots1().getData()[i], x1Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(1).getData()[i], x1Values[i], ref * EPS);
}
for (int i = 0; i < n0Data - 1; ++i) {
for (int j = 0; j < n1Data - 1; ++j) {
for (int k = 0; k < orderExp; ++k) {
for (int l = 0; l < orderExp; ++l) {
final double ref = Math.abs(coefsExp[i][j].getData()[k][l]) == 0. ? 1. : Math.abs(coefsExp[i][j].getData()[k][l]);
assertEquals(result.getCoefs()[i][j].getData()[k][l], coefsExp[i][j].getData()[k][l], ref * EPS);
}
}
}
}
double[][] resValues = interp.interpolate(x0Values, x1Values, yValues, x0Keys, x1Keys).getData();
for (int i = 0; i < n0Keys; ++i) {
for (int j = 0; j < n1Keys; ++j) {
final double expVal = (x0Keys[i] + 2.) * (x1Keys[j] + 5.);
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resValues[i][j], expVal, ref * EPS);
}
}
// final PiecewisePolynomialFunction2D func = new PiecewisePolynomialFunction2D();
for (int i = 0; i < n0Keys; ++i) {
for (int j = 0; j < n1Keys; ++j) {
final double expVal = (x0Keys[i] + 2.) * (x1Keys[j] + 5.);
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resValues[i][j], expVal, ref * EPS);
// assertEquals(resValues[i][j], func.evaluate(result, x0Keys[i], x1Keys[j]), ref * EPS);
}
}
{
final double expVal = (x0Keys[1] + 2.) * (x1Keys[2] + 5.);
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(interp.interpolate(x0Values, x1Values, yValues, x0Keys[1], x1Keys[2]), expVal, ref * EPS);
}
{
final double expVal = (x0Keys[23] + 2.) * (x1Keys[20] + 5.);
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(interp.interpolate(x0Values, x1Values, yValues, x0Keys[23], x1Keys[20]), expVal, ref * EPS);
}
// for (int i = 0; i < n0Keys; ++i) {
// System.out.print("\t" + x0Keys[i]);
// }
// System.out.print("\n");
// for (int j = 0; j < n1Keys; ++j) {
// System.out.print(x1Keys[j]);
// for (int i = 0; i < n0Keys; ++i) {
// System.out.print("\t" + values[i][j]);
// }
// System.out.print("\n");
// }
//
// System.out.print("\n");
}
/**
* f(x0,x1) = ( x0 - 1.5)^2 * (x1 - 2.)^2
*/
@Test
public void quadraticTest() {
double[] x0Values = new double[] {1., 2., 3., 4. };
double[] x1Values = new double[] {-1., 0., 1., 2., 3. };
final int n0Data = x0Values.length;
final int n1Data = x1Values.length;
double[][] yValues = new double[n0Data][n1Data];
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
yValues[i][j] = (x0Values[i] - 1.5) * (x0Values[i] - 1.5) * (x1Values[j] - 2.) * (x1Values[j] - 2.);
}
}
CubicSplineInterpolator method = new CubicSplineInterpolator();
PiecewisePolynomialInterpolator2D interp = new BicubicSplineInterpolator(method);
PiecewisePolynomialResult2D result = interp.interpolate(x0Values, x1Values, yValues);
final int n0IntExp = n0Data - 1;
final int n1IntExp = n1Data - 1;
final int orderExp = 4;
final int n0Keys = 51;
final int n1Keys = 61;
double[] x0Keys = new double[n0Keys];
double[] x1Keys = new double[n1Keys];
for (int i = 0; i < n0Keys; ++i) {
x0Keys[i] = 0. + 5. * i / (n0Keys - 1);
}
for (int i = 0; i < n1Keys; ++i) {
x1Keys[i] = -2. + 6. * i / (n1Keys - 1);
}
assertEquals(result.getNumberOfIntervals()[0], n0IntExp);
assertEquals(result.getNumberOfIntervals()[1], n1IntExp);
assertEquals(result.getOrder()[0], orderExp);
assertEquals(result.getOrder()[1], orderExp);
for (int i = 0; i < n0Data; ++i) {
final double ref = Math.abs(x0Values[i]) == 0. ? 1. : Math.abs(x0Values[i]);
assertEquals(result.getKnots0().getData()[i], x0Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(0).getData()[i], x0Values[i], ref * EPS);
}
for (int i = 0; i < n1Data; ++i) {
final double ref = Math.abs(x1Values[i]) == 0. ? 1. : Math.abs(x1Values[i]);
assertEquals(result.getKnots1().getData()[i], x1Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(1).getData()[i], x1Values[i], ref * EPS);
}
for (int i = 0; i < n0Data - 1; ++i) {
for (int j = 0; j < n1Data - 1; ++j) {
final double ref = Math.abs(yValues[i][j]) == 0. ? 1. : Math.abs(yValues[i][j]);
assertEquals(result.getCoefs()[i][j].getData()[orderExp - 1][orderExp - 1], yValues[i][j], ref * EPS);
}
}
double[][] resValues = interp.interpolate(x0Values, x1Values, yValues, x0Values, x1Values).getData();
final PiecewisePolynomialFunction2D func2D = new PiecewisePolynomialFunction2D();
double[][] resDiffX0 = func2D.differentiateX0(result, x0Values, x1Values).getData();
double[][] resDiffX1 = func2D.differentiateX1(result, x0Values, x1Values).getData();
final PiecewisePolynomialFunction1D func1D = new PiecewisePolynomialFunction1D();
double[][] expDiffX0 = func1D.differentiate(method.interpolate(x0Values, OG_ALGEBRA.getTranspose(new DoubleMatrix2D(yValues)).getData()), x0Values).getData();
double[][] expDiffX1 = func1D.differentiate(method.interpolate(x1Values, yValues), x1Values).getData();
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = expDiffX1[i][j];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resDiffX1[i][j], expVal, ref * EPS);
}
}
// System.out.println(new DoubleMatrix2D(expDiffX0));
// System.out.println(new DoubleMatrix2D(resDiffX0));
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = expDiffX0[j][i];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resDiffX0[i][j], expVal, ref * EPS);
}
}
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = yValues[i][j];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resValues[i][j], expVal, ref * EPS);
}
}
}
/**
* f(x0,x1) = ( x0 - 1.)^3 * (x1 + 14./13.)^3
*/
@Test
public void cubicTest() {
double[] x0Values = new double[] {1., 2., 3., 4. };
double[] x1Values = new double[] {-1., 0., 1., 2., 3. };
final int n0Data = x0Values.length;
final int n1Data = x1Values.length;
double[][] yValues = new double[n0Data][n1Data];
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
yValues[i][j] = (x0Values[i] - 1.) * (x0Values[i] - 1.) * (x0Values[i] - 1.) * (x1Values[j] + 14. / 13.) * (x1Values[j] + 14. / 13.) * (x1Values[j] + 14. / 13.);
}
}
CubicSplineInterpolator method = new CubicSplineInterpolator();
PiecewisePolynomialInterpolator2D interp = new BicubicSplineInterpolator(method);
PiecewisePolynomialResult2D result = interp.interpolate(x0Values, x1Values, yValues);
final int n0IntExp = n0Data - 1;
final int n1IntExp = n1Data - 1;
final int orderExp = 4;
final int n0Keys = 51;
final int n1Keys = 61;
double[] x0Keys = new double[n0Keys];
double[] x1Keys = new double[n1Keys];
for (int i = 0; i < n0Keys; ++i) {
x0Keys[i] = 0. + 5. * i / (n0Keys - 1);
}
for (int i = 0; i < n1Keys; ++i) {
x1Keys[i] = -2. + 6. * i / (n1Keys - 1);
}
assertEquals(result.getNumberOfIntervals()[0], n0IntExp);
assertEquals(result.getNumberOfIntervals()[1], n1IntExp);
assertEquals(result.getOrder()[0], orderExp);
assertEquals(result.getOrder()[1], orderExp);
for (int i = 0; i < n0Data; ++i) {
final double ref = Math.abs(x0Values[i]) == 0. ? 1. : Math.abs(x0Values[i]);
assertEquals(result.getKnots0().getData()[i], x0Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(0).getData()[i], x0Values[i], ref * EPS);
}
for (int i = 0; i < n1Data; ++i) {
final double ref = Math.abs(x1Values[i]) == 0. ? 1. : Math.abs(x1Values[i]);
assertEquals(result.getKnots1().getData()[i], x1Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(1).getData()[i], x1Values[i], ref * EPS);
}
for (int i = 0; i < n0Data - 1; ++i) {
for (int j = 0; j < n1Data - 1; ++j) {
final double ref = Math.abs(yValues[i][j]) == 0. ? 1. : Math.abs(yValues[i][j]);
assertEquals(result.getCoefs()[i][j].getData()[orderExp - 1][orderExp - 1], yValues[i][j], ref * EPS);
}
}
double[][] resValues = interp.interpolate(x0Values, x1Values, yValues, x0Values, x1Values).getData();
final PiecewisePolynomialFunction2D func2D = new PiecewisePolynomialFunction2D();
double[][] resDiffX0 = func2D.differentiateX0(result, x0Values, x1Values).getData();
double[][] resDiffX1 = func2D.differentiateX1(result, x0Values, x1Values).getData();
final PiecewisePolynomialFunction1D func1D = new PiecewisePolynomialFunction1D();
double[][] expDiffX0 = func1D.differentiate(method.interpolate(x0Values, OG_ALGEBRA.getTranspose(new DoubleMatrix2D(yValues)).getData()), x0Values).getData();
double[][] expDiffX1 = func1D.differentiate(method.interpolate(x1Values, yValues), x1Values).getData();
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = expDiffX1[i][j];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resDiffX1[i][j], expVal, ref * EPS);
}
}
// System.out.println(new DoubleMatrix2D(expDiffX0));
// System.out.println(new DoubleMatrix2D(resDiffX0));
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = expDiffX0[j][i];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resDiffX0[i][j], expVal, ref * EPS);
}
}
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = yValues[i][j];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resValues[i][j], expVal, ref * EPS);
}
}
}
/**
*
*/
@Test
public void crossDerivativeTest() {
double[] x0Values = new double[] {1., 2., 3., 4. };
double[] x1Values = new double[] {-1., 0., 1., 2., 3. };
final int n0Data = x0Values.length;
final int n1Data = x1Values.length;
double[][] yValues = new double[][] { {1.0, -1.0, 0.0, 1.0, 0.0, }, {1.0, -1.0, 0.0, 1.0, -2.0 }, {1.0, -2.0, 0.0, -2.0, -2.0 }, {-1.0, -1.0, -2.0, -2.0, -1.0 } };
NaturalSplineInterpolator method = new NaturalSplineInterpolator();
PiecewisePolynomialInterpolator2D interp = new BicubicSplineInterpolator(method);
PiecewisePolynomialResult2D result = interp.interpolate(x0Values, x1Values, yValues);
final int n0IntExp = n0Data - 1;
final int n1IntExp = n1Data - 1;
final int orderExp = 4;
final int n0Keys = 51;
final int n1Keys = 61;
double[] x0Keys = new double[n0Keys];
double[] x1Keys = new double[n1Keys];
for (int i = 0; i < n0Keys; ++i) {
x0Keys[i] = 0. + 5. * i / (n0Keys - 1);
}
for (int i = 0; i < n1Keys; ++i) {
x1Keys[i] = -2. + 6. * i / (n1Keys - 1);
}
assertEquals(result.getNumberOfIntervals()[0], n0IntExp);
assertEquals(result.getNumberOfIntervals()[1], n1IntExp);
assertEquals(result.getOrder()[0], orderExp);
assertEquals(result.getOrder()[1], orderExp);
for (int i = 0; i < n0Data; ++i) {
final double ref = Math.abs(x0Values[i]) == 0. ? 1. : Math.abs(x0Values[i]);
assertEquals(result.getKnots0().getData()[i], x0Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(0).getData()[i], x0Values[i], ref * EPS);
}
for (int i = 0; i < n1Data; ++i) {
final double ref = Math.abs(x1Values[i]) == 0. ? 1. : Math.abs(x1Values[i]);
assertEquals(result.getKnots1().getData()[i], x1Values[i], ref * EPS);
assertEquals(result.getKnots2D().get(1).getData()[i], x1Values[i], ref * EPS);
}
for (int i = 0; i < n0Data - 1; ++i) {
for (int j = 0; j < n1Data - 1; ++j) {
final double ref = Math.abs(yValues[i][j]) == 0. ? 1. : Math.abs(yValues[i][j]);
assertEquals(result.getCoefs()[i][j].getData()[orderExp - 1][orderExp - 1], yValues[i][j], ref * EPS);
}
}
double[][] resValues = interp.interpolate(x0Values, x1Values, yValues, x0Values, x1Values).getData();
final PiecewisePolynomialFunction2D func2D = new PiecewisePolynomialFunction2D();
double[][] resDiffX0 = func2D.differentiateX0(result, x0Values, x1Values).getData();
double[][] resDiffX1 = func2D.differentiateX1(result, x0Values, x1Values).getData();
final PiecewisePolynomialFunction1D func1D = new PiecewisePolynomialFunction1D();
double[][] expDiffX0 = func1D.differentiate(method.interpolate(x0Values, OG_ALGEBRA.getTranspose(new DoubleMatrix2D(yValues)).getData()), x0Values).getData();
double[][] expDiffX1 = func1D.differentiate(method.interpolate(x1Values, yValues), x1Values).getData();
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = expDiffX1[i][j];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resDiffX1[i][j], expVal, ref * EPS);
}
}
// System.out.println(new DoubleMatrix2D(expDiffX0));
// System.out.println(new DoubleMatrix2D(resDiffX0));
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = expDiffX0[j][i];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resDiffX0[i][j], expVal, ref * EPS);
}
}
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
final double expVal = yValues[i][j];
final double ref = Math.abs(expVal) == 0. ? 1. : Math.abs(expVal);
assertEquals(resValues[i][j], expVal, ref * EPS);
}
}
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void nullx0Test() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
x0Values = null;
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void nullx1Test() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
x1Values = null;
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void nullyTest() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
yValues = null;
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void wrongLengthx0Test() {
double[] x0Values = new double[] {0., 1., 2. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void wrongLengthx1Test() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2., 3. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void shortx0Test() {
double[] x0Values = new double[] {1. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] {{1., 2., 4. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void shortx1Test() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0. };
double[][] yValues = new double[][] { {1. }, {-1. }, {2. }, {5. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void infX0Test() {
double[] x0Values = new double[] {0., 1., 2., INF };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void nanX0Test() {
double[] x0Values = new double[] {0., 1., 2., Double.NaN };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void infX1Test() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., INF };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void nanX1Test() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., Double.NaN };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void infYTest() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., INF }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void nanYTest() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., Double.NaN } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void coincideX0Test() {
double[] x0Values = new double[] {0., 1., 1., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void coincideX1Test() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 1. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void notTwoMethodsTest() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1., 2., 4. }, {-1., 2., -4. }, {2., 3., 4. }, {5., 2., 1. } };
BicubicSplineInterpolator interp = new BicubicSplineInterpolator(new PiecewisePolynomialInterpolator[] {new CubicSplineInterpolator() });
interp.interpolate(x0Values, x1Values, yValues);
}
/**
*
*/
@Test(expectedExceptions = IllegalArgumentException.class)
public void notKnotRevoveredTests() {
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1.e-20, 3.e-120, 5.e120 }, {2.e-20, 3.e-120, 4.e-120 }, {1.e-20, 1.e-120, 1.e-20 }, {4.e-120, 3.e-20, 2.e-20 } };
BicubicSplineInterpolator intp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
intp.interpolate(x0Values, x1Values, yValues);
}
/**
* Tests below for debugging
*/
@Test
(enabled = false)
public void printTest() {
// double[] x0Values = new double[] {0., 1., 2., 3. };
// double[] x1Values = new double[] {0., 0.000000000001, 2. };
double[] x0Values = new double[] {0., 1., 2., 3. };
double[] x1Values = new double[] {0., 1., 2. };
double[][] yValues = new double[][] { {1.e-20, 3.e-120, 5.e-20 }, {2.e-20, 3.e-120, 4.e-120 }, {1.e-20, 1.e-120, 1.e-20 }, {4.e-120, 3.e-20, 2.e-20 } };
// double[] x0Values = new double[] {0., 1., 2. };
// double[] x1Values = new double[] {0., 1., 2., 3. };
// double[][] yValues = new double[][] { {1., 3., 5., 7. }, {2., 3., 4., 5. }, {1., 1., 1., 1. } };
BicubicSplineInterpolator intp = new BicubicSplineInterpolator(new CubicSplineInterpolator());
PiecewisePolynomialResult2D result2D = intp.interpolate(x0Values, x1Values, yValues);
System.out.println(result2D.getCoefs()[0][0]);
System.out.println(result2D.getCoefs()[2][1]);
final int n0Keys = 31;
final int n1Keys = 21;
double[] x0Keys = new double[n0Keys];
double[] x1Keys = new double[n1Keys];
for (int i = 0; i < n0Keys; ++i) {
x0Keys[i] = 0. + 3. * i / (n0Keys - 1);
}
for (int i = 0; i < n1Keys; ++i) {
x1Keys[i] = 0. + 2. * i / (n1Keys - 1);
}
// final int n0Keys = 61;
// final int n1Keys = 101;
// double[] x0Keys = new double[n0Keys];
// double[] x1Keys = new double[n1Keys];
// for (int i = 0; i < n0Keys; ++i) {
// x0Keys[i] = -1. + 4. * i / (n0Keys - 1);
// }
// for (int i = 0; i < n1Keys; ++i) {
// x1Keys[i] = -1. + 5. * i / (n1Keys - 1);
// }
PiecewisePolynomialFunction2D func = new PiecewisePolynomialFunction2D();
final double[][] values = func.evaluate(result2D, x0Keys, x1Keys).getData();
for (int i = 0; i < n0Keys; ++i) {
System.out.print("\t" + x0Keys[i]);
}
System.out.print("\n");
for (int j = 0; j < n1Keys; ++j) {
System.out.print(x1Keys[j]);
for (int i = 0; i < n0Keys; ++i) {
System.out.print("\t" + values[i][j]);
}
System.out.print("\n");
}
System.out.print("\n");
for (int i = 0; i < x0Values.length; ++i) {
System.out.print("\t" + x0Values[i]);
}
System.out.print("\n");
for (int j = 0; j < x1Values.length; ++j) {
System.out.print(x1Values[j]);
for (int i = 0; i < x0Values.length; ++i) {
System.out.print("\t" + yValues[i][j]);
}
System.out.print("\n");
}
System.out.print("\n");
}
/**
*
*/
@Test
(enabled = false)
public void randomTest() {
double[] x0Values = new double[] {1., 2., 3., 4. };
double[] x1Values = new double[] {-1., 0., 1., 2., 3. };
final int n0Data = x0Values.length;
final int n1Data = x1Values.length;
double[][] yValues = new double[n0Data][n1Data];
final Random randObj = new Random();
int k = 0;
while (k < 100000) {
for (int i = 0; i < n0Data; ++i) {
for (int j = 0; j < n1Data; ++j) {
yValues[i][j] = randObj.nextInt(4) - 2.;
}
}
System.out.println(new DoubleMatrix2D(yValues));
NaturalSplineInterpolator method = new NaturalSplineInterpolator();
PiecewisePolynomialInterpolator2D interp = new BicubicSplineInterpolator(method);
interp.interpolate(x0Values, x1Values, yValues);
++k;
}
}
}