Author: luc Date: Sun Feb 1 21:13:55 2009 New Revision: 739840 URL: http://svn.apache.org/viewvc?rev=739840&view=rev Log: added a PolynomialsUtils class providing factory methods for Chebyshev, Hermite, Laguerre and Legendre polynomials the code was extracted from mantissa and modified
Added: commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.java (with props) commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/polynomials/PolynomialsUtilsTest.java (with props) Removed: commons/proper/math/trunk/src/mantissa/src/org/spaceroots/mantissa/algebra/Chebyshev.java commons/proper/math/trunk/src/mantissa/src/org/spaceroots/mantissa/algebra/CoefficientsGenerator.java commons/proper/math/trunk/src/mantissa/src/org/spaceroots/mantissa/algebra/Hermite.java commons/proper/math/trunk/src/mantissa/src/org/spaceroots/mantissa/algebra/Laguerre.java commons/proper/math/trunk/src/mantissa/src/org/spaceroots/mantissa/algebra/Legendre.java commons/proper/math/trunk/src/mantissa/src/org/spaceroots/mantissa/algebra/OrthogonalPolynomial.java commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/ChebyshevTest.java commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/HermiteTest.java commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/LaguerreTest.java commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/LegendreTest.java Modified: commons/proper/math/trunk/src/java/org/apache/commons/math/fraction/Fraction.java commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/AllTests.java commons/proper/math/trunk/src/site/xdoc/changes.xml commons/proper/math/trunk/src/site/xdoc/userguide/analysis.xml Added: commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.java URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.java?rev=739840&view=auto ============================================================================== --- commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.java (added) +++ commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.java Sun Feb 1 21:13:55 2009 @@ -0,0 +1,280 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.commons.math.analysis.polynomials; + +import java.util.ArrayList; + +import org.apache.commons.math.fraction.Fraction; + +/** + * A collection of static methods that operate on or return polynomials. + * + * @version $Revision$ $Date$ + * @since 2.0 + */ +public class PolynomialsUtils { + + /** Coefficients for Chebyshev polynomials. */ + private static final ArrayList<Fraction> CHEBYSHEV_COEFFICIENTS; + + /** Coefficients for Hermite polynomials. */ + private static final ArrayList<Fraction> HERMITE_COEFFICIENTS; + + /** Coefficients for Laguerre polynomials. */ + private static final ArrayList<Fraction> LAGUERRE_COEFFICIENTS; + + /** Coefficients for Legendre polynomials. */ + private static final ArrayList<Fraction> LEGENDRE_COEFFICIENTS; + + static { + + // initialize recurrence for Chebyshev polynomials + // T0(X) = 1, T1(X) = 0 + 1 * X + CHEBYSHEV_COEFFICIENTS = new ArrayList<Fraction>(); + CHEBYSHEV_COEFFICIENTS.add(Fraction.ONE); + CHEBYSHEV_COEFFICIENTS.add(Fraction.ZERO); + CHEBYSHEV_COEFFICIENTS.add(Fraction.ONE); + + // initialize recurrence for Hermite polynomials + // H0(X) = 1, H1(X) = 0 + 2 * X + HERMITE_COEFFICIENTS = new ArrayList<Fraction>(); + HERMITE_COEFFICIENTS.add(Fraction.ONE); + HERMITE_COEFFICIENTS.add(Fraction.ZERO); + HERMITE_COEFFICIENTS.add(Fraction.TWO); + + // initialize recurrence for Laguerre polynomials + // L0(X) = 1, L1(X) = 1 - 1 * X + LAGUERRE_COEFFICIENTS = new ArrayList<Fraction>(); + LAGUERRE_COEFFICIENTS.add(Fraction.ONE); + LAGUERRE_COEFFICIENTS.add(Fraction.ONE); + LAGUERRE_COEFFICIENTS.add(Fraction.MINUS_ONE); + + // initialize recurrence for Legendre polynomials + // P0(X) = 1, P1(X) = 0 + 1 * X + LEGENDRE_COEFFICIENTS = new ArrayList<Fraction>(); + LEGENDRE_COEFFICIENTS.add(Fraction.ONE); + LEGENDRE_COEFFICIENTS.add(Fraction.ZERO); + LEGENDRE_COEFFICIENTS.add(Fraction.ONE); + + } + + /** + * Private constructor, to prevent instantiation. + */ + private PolynomialsUtils() { + } + + /** + * Create a Chebyshev polynomial of the first kind. + * <p><a href="http://mathworld.wolfram.com/ChebyshevPolynomialoftheFirstKind.html">Chebyshev + * polynomials of the first kind</a> are orthogonal polynomials. + * They can be defined by the following recurrence relations: + * <pre> + * T<sub>0</sub>(X) = 1 + * T<sub>1</sub>(X) = X + * T<sub>k+1</sub>(X) = 2X T<sub>k</sub>(X) - T<sub>k-1</sub>(X) + * </pre></p> + * @param degree degree of the polynomial + * @return Chebyshev polynomial of specified degree + */ + public static PolynomialFunction createChebyshevPolynomial(final int degree) { + return buildPolynomial(degree, CHEBYSHEV_COEFFICIENTS, + new RecurrenceCoefficientsGenerator() { + private final Fraction[] coeffs = { Fraction.ZERO, Fraction.TWO, Fraction.ONE}; + /** {...@inheritdoc} */ + public Fraction[] generate(int k) { + return coeffs; + } + }); + } + + /** + * Create a Hermite polynomial. + * <p><a href="http://mathworld.wolfram.com/HermitePolynomial.html">Hermite + * polynomials</a> are orthogonal polynomials. + * They can be defined by the following recurrence relations: + * <pre> + * H<sub>0</sub>(X) = 1 + * H<sub>1</sub>(X) = 2X + * H<sub>k+1</sub>(X) = 2X H<sub>k</sub>(X) - 2k H<sub>k-1</sub>(X) + * </pre></p> + + * @param degree degree of the polynomial + * @return Hermite polynomial of specified degree + */ + public static PolynomialFunction createHermitePolynomial(final int degree) { + return buildPolynomial(degree, HERMITE_COEFFICIENTS, + new RecurrenceCoefficientsGenerator() { + /** {...@inheritdoc} */ + public Fraction[] generate(int k) { + return new Fraction[] { + Fraction.ZERO, + Fraction.TWO, + new Fraction(2 * k, 1)}; + } + }); + } + + /** + * Create a Laguerre polynomial. + * <p><a href="http://mathworld.wolfram.com/LaguerrePolynomial.html">Laguerre + * polynomials</a> are orthogonal polynomials. + * They can be defined by the following recurrence relations: + * <pre> + * L<sub>0</sub>(X) = 1 + * L<sub>1</sub>(X) = 1 - X + * (k+1) L<sub>k+1</sub>(X) = (2k + 1 - X) L<sub>k</sub>(X) - k L<sub>k-1</sub>(X) + * </pre></p> + * @param degree degree of the polynomial + * @return Laguerre polynomial of specified degree + */ + public static PolynomialFunction createLaguerrePolynomial(final int degree) { + return buildPolynomial(degree, LAGUERRE_COEFFICIENTS, + new RecurrenceCoefficientsGenerator() { + /** {...@inheritdoc} */ + public Fraction[] generate(int k) { + final int kP1 = k + 1; + return new Fraction[] { + new Fraction(2 * k + 1, kP1), + new Fraction(-1, kP1), + new Fraction(k, kP1)}; + } + }); + } + + /** + * Create a Legendre polynomial. + * <p><a href="http://mathworld.wolfram.com/LegendrePolynomial.html">Legendre + * polynomials</a> are orthogonal polynomials. + * They can be defined by the following recurrence relations: + * <pre> + * P<sub>0</sub>(X) = 1 + * P<sub>1</sub>(X) = X + * (k+1) P<sub>k+1</sub>(X) = (2k+1) X P<sub>k</sub>(X) - k P<sub>k-1</sub>(X) + * </pre></p> + * @param degree degree of the polynomial + * @return Legendre polynomial of specified degree + */ + public static PolynomialFunction createLegendrePolynomial(final int degree) { + return buildPolynomial(degree, LEGENDRE_COEFFICIENTS, + new RecurrenceCoefficientsGenerator() { + /** {...@inheritdoc} */ + public Fraction[] generate(int k) { + final int kP1 = k + 1; + return new Fraction[] { + Fraction.ZERO, + new Fraction(k + kP1, kP1), + new Fraction(k, kP1)}; + } + }); + } + + /** Get the coefficients array for a given degree. + * @param degree degree of the polynomial + * @param coefficients list where the computed coefficients are stored + * @param generator recurrence coefficients generator + * @return coefficients array + */ + private static PolynomialFunction buildPolynomial(final int degree, + final ArrayList<Fraction> coefficients, + final RecurrenceCoefficientsGenerator generator) { + + final int maxDegree = (int) Math.floor(Math.sqrt(2 * coefficients.size())) - 1; + synchronized (PolynomialsUtils.class) { + if (degree > maxDegree) { + computeUpToDegree(degree, maxDegree, generator, coefficients); + } + } + + // coefficient for polynomial 0 is l [0] + // coefficients for polynomial 1 are l [1] ... l [2] (degrees 0 ... 1) + // coefficients for polynomial 2 are l [3] ... l [5] (degrees 0 ... 2) + // coefficients for polynomial 3 are l [6] ... l [9] (degrees 0 ... 3) + // coefficients for polynomial 4 are l[10] ... l[14] (degrees 0 ... 4) + // coefficients for polynomial 5 are l[15] ... l[20] (degrees 0 ... 5) + // coefficients for polynomial 6 are l[21] ... l[27] (degrees 0 ... 6) + // ... + final int start = degree * (degree + 1) / 2; + + final double[] a = new double[degree + 1]; + for (int i = 0; i <= degree; ++i) { + a[i] = coefficients.get(start + i).doubleValue(); + } + + // build the polynomial + return new PolynomialFunction(a); + + } + + /** Compute polynomial coefficients up to a given degree. + * @param degree maximal degree + * @param maxDegree current maximal degree + * @param generator recurrence coefficients generator + * @param coefficients list where the computed coefficients should be appended + */ + private static void computeUpToDegree(final int degree, final int maxDegree, + final RecurrenceCoefficientsGenerator generator, + final ArrayList<Fraction> coefficients) { + + int startK = (maxDegree - 1) * maxDegree / 2; + for (int k = maxDegree; k < degree; ++k) { + + // start indices of two previous polynomials Pk(X) and Pk-1(X) + int startKm1 = startK; + startK += k; + + // Pk+1(X) = (a[0] + a[1] X) Pk(X) - a[2] Pk-1(X) + Fraction[] ai = generator.generate(k); + + Fraction ck = coefficients.get(startK); + Fraction ckm1 = coefficients.get(startKm1); + + // degree 0 coefficient + coefficients.add(ck.multiply(ai[0]).subtract(ckm1.multiply(ai[2]))); + + // degree 1 to degree k-1 coefficients + for (int i = 1; i < k; ++i) { + final Fraction ckPrev = ck; + ck = coefficients.get(startK + i); + ckm1 = coefficients.get(startKm1 + i); + coefficients.add(ck.multiply(ai[0]).add(ckPrev.multiply(ai[1])).subtract(ckm1.multiply(ai[2]))); + } + + // degree k coefficient + final Fraction ckPrev = ck; + ck = coefficients.get(startK + k); + coefficients.add(ck.multiply(ai[0]).add(ckPrev.multiply(ai[1]))); + + // degree k+1 coefficient + coefficients.add(ck.multiply(ai[1])); + + } + + } + + /** Interface for recurrence coefficients generation. */ + private static interface RecurrenceCoefficientsGenerator { + /** + * Generate recurrence coefficients. + * @param k highest degree of the polynomials used in the recurrence + * @return an array of three coefficients such that + * P<sub>k+1</sub>(X) = (a[0] + a[1] X) P<sub>k</sub>(X) - a[2] P<sub>k-1</sub>(X) + */ + Fraction[] generate(int k); + } + +} Propchange: commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.java ------------------------------------------------------------------------------ svn:eol-style = native Propchange: commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.java ------------------------------------------------------------------------------ svn:keywords = Author Date Id Revision Modified: commons/proper/math/trunk/src/java/org/apache/commons/math/fraction/Fraction.java URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/java/org/apache/commons/math/fraction/Fraction.java?rev=739840&r1=739839&r2=739840&view=diff ============================================================================== --- commons/proper/math/trunk/src/java/org/apache/commons/math/fraction/Fraction.java (original) +++ commons/proper/math/trunk/src/java/org/apache/commons/math/fraction/Fraction.java Sun Feb 1 21:13:55 2009 @@ -29,15 +29,21 @@ */ public class Fraction extends Number implements Comparable<Fraction> { + /** A fraction representing "2 / 1". */ + public static final Fraction TWO = new Fraction(2, 1); + /** A fraction representing "1 / 1". */ public static final Fraction ONE = new Fraction(1, 1); /** A fraction representing "0 / 1". */ public static final Fraction ZERO = new Fraction(0, 1); + /** A fraction representing "-1 / 1". */ + public static final Fraction MINUS_ONE = new Fraction(-1, 1); + /** Serializable version identifier */ - private static final long serialVersionUID = -5731055832688548463L; - + private static final long serialVersionUID = 3071409609509774764L; + /** The denominator. */ private final int denominator; @@ -145,7 +151,7 @@ return; } - long p0 = 1; + long p0 = 1; long q0 = 0; long p1 = a0; long q1 = 1; @@ -197,7 +203,7 @@ * reduced to lowest terms. * @param num the numerator. * @param den the denominator. - * @throws ArithmeticException if the denomiator is <code>zero</code> + * @throws ArithmeticException if the denominator is <code>zero</code> */ public Fraction(int num, int den) { super(); Modified: commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/AllTests.java URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/AllTests.java?rev=739840&r1=739839&r2=739840&view=diff ============================================================================== --- commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/AllTests.java (original) +++ commons/proper/math/trunk/src/mantissa/tests-src/org/spaceroots/mantissa/algebra/AllTests.java Sun Feb 1 21:13:55 2009 @@ -28,10 +28,6 @@ suite.addTest(RationalNumberTest.suite()); suite.addTest(PolynomialRationalTest.suite()); suite.addTest(PolynomialDoubleTest.suite()); - suite.addTest(ChebyshevTest.suite()); - suite.addTest(HermiteTest.suite()); - suite.addTest(LegendreTest.suite()); - suite.addTest(LaguerreTest.suite()); suite.addTest(PolynomialFractionTest.suite()); return suite; Modified: commons/proper/math/trunk/src/site/xdoc/changes.xml URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/site/xdoc/changes.xml?rev=739840&r1=739839&r2=739840&view=diff ============================================================================== --- commons/proper/math/trunk/src/site/xdoc/changes.xml (original) +++ commons/proper/math/trunk/src/site/xdoc/changes.xml Sun Feb 1 21:13:55 2009 @@ -40,6 +40,9 @@ <body> <release version="2.0" date="TBD" description="TBD"> <action dev="luc" type="add" > + Added factory methods to create Chebyshev, Hermite, Laguerre and Legendre polynomials. + </action> + <action dev="luc" type="add" > Added add, subtract, negate, multiply and toString methods to PolynomialFunction. </action> <action dev="psteitz" type="update" issue="MATH-189"> Modified: commons/proper/math/trunk/src/site/xdoc/userguide/analysis.xml URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/site/xdoc/userguide/analysis.xml?rev=739840&r1=739839&r2=739840&view=diff ============================================================================== --- commons/proper/math/trunk/src/site/xdoc/userguide/analysis.xml (original) +++ commons/proper/math/trunk/src/site/xdoc/userguide/analysis.xml Sun Feb 1 21:13:55 2009 @@ -319,10 +319,20 @@ </subsection> <subsection name="4.6 Polynomials" href="polynomials"> <p> - The <a href="../apidocs/org/apache/commons/math/analysis/polynomials/package.html"> + The <a href="../apidocs/org/apache/commons/math/analysis/polynomials/package-summary.html"> org.apache.commons.math.analysis.polynomials</a> package provides real coefficients polynomials. </p> + <p> + The <a href="../apidocs/org/apache/commons/math/analysis/polynomials/PolynomialFunction.html"> + org.apache.commons.math.analysis.polynomials.PolynomialFunction</a> class is the most general + one, using traditional coefficients arrays. The <a + href="../apidocs/org/apache/commons/math/analysis/polynomials/PolynomialsUtils.html"> + org.apache.commons.math.analysis.polynomials.PolynomialsUtils</a> utility class provides static + factory methods to build Chebyshev, Hermite, Lagrange and Legendre polynomials. Beware that due + to overflows in the coefficients computations, these factory methods can only build low degrees + polynomials yet. + </p> </subsection> </section> </body> Added: commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/polynomials/PolynomialsUtilsTest.java URL: http://svn.apache.org/viewvc/commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/polynomials/PolynomialsUtilsTest.java?rev=739840&view=auto ============================================================================== --- commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/polynomials/PolynomialsUtilsTest.java (added) +++ commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/polynomials/PolynomialsUtilsTest.java Sun Feb 1 21:13:55 2009 @@ -0,0 +1,225 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.commons.math.analysis.polynomials; + +import junit.framework.TestCase; + +/** + * Tests the PolynomialsUtils class. + * + * @version $Revision$ $Date$ + */ +public class PolynomialsUtilsTest extends TestCase { + + public void testFirstChebyshevPolynomials() { + + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(3), "-3.0 x + 4.0 x^3"); + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(2), "-1.0 + 2.0 x^2"); + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(1), "x"); + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(0), "1.0"); + + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(7), "-7.0 x + 56.0 x^3 - 112.0 x^5 + 64.0 x^7"); + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(6), "-1.0 + 18.0 x^2 - 48.0 x^4 + 32.0 x^6"); + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(5), "5.0 x - 20.0 x^3 + 16.0 x^5"); + checkPolynomial(PolynomialsUtils.createChebyshevPolynomial(4), "1.0 - 8.0 x^2 + 8.0 x^4"); + + } + + public void testChebyshevBounds() { + for (int k = 0; k < 12; ++k) { + PolynomialFunction Tk = PolynomialsUtils.createChebyshevPolynomial(k); + for (double x = -1.0; x <= 1.0; x += 0.02) { + assertTrue(k + " " + Tk.value(x), Math.abs(Tk.value(x)) < (1.0 + 1.0e-12)); + } + } + } + + public void testChebyshevDifferentials() { + for (int k = 0; k < 12; ++k) { + + PolynomialFunction Tk0 = PolynomialsUtils.createChebyshevPolynomial(k); + PolynomialFunction Tk1 = Tk0.polynomialDerivative(); + PolynomialFunction Tk2 = Tk1.polynomialDerivative(); + + PolynomialFunction g0 = new PolynomialFunction(new double[] { k * k }); + PolynomialFunction g1 = new PolynomialFunction(new double[] { 0, -1}); + PolynomialFunction g2 = new PolynomialFunction(new double[] { 1, 0, -1 }); + + PolynomialFunction Tk0g0 = Tk0.multiply(g0); + PolynomialFunction Tk1g1 = Tk1.multiply(g1); + PolynomialFunction Tk2g2 = Tk2.multiply(g2); + + checkNullPolynomial(Tk0g0.add(Tk1g1.add(Tk2g2))); + + } + } + + public void testFirstHermitePolynomials() { + + checkPolynomial(PolynomialsUtils.createHermitePolynomial(3), "-12.0 x + 8.0 x^3"); + checkPolynomial(PolynomialsUtils.createHermitePolynomial(2), "-2.0 + 4.0 x^2"); + checkPolynomial(PolynomialsUtils.createHermitePolynomial(1), "2.0 x"); + checkPolynomial(PolynomialsUtils.createHermitePolynomial(0), "1.0"); + + checkPolynomial(PolynomialsUtils.createHermitePolynomial(7), "-1680.0 x + 3360.0 x^3 - 1344.0 x^5 + 128.0 x^7"); + checkPolynomial(PolynomialsUtils.createHermitePolynomial(6), "-120.0 + 720.0 x^2 - 480.0 x^4 + 64.0 x^6"); + checkPolynomial(PolynomialsUtils.createHermitePolynomial(5), "120.0 x - 160.0 x^3 + 32.0 x^5"); + checkPolynomial(PolynomialsUtils.createHermitePolynomial(4), "12.0 - 48.0 x^2 + 16.0 x^4"); + + } + + public void testHermiteDifferentials() { + for (int k = 0; k < 12; ++k) { + + PolynomialFunction Hk0 = PolynomialsUtils.createHermitePolynomial(k); + PolynomialFunction Hk1 = Hk0.polynomialDerivative(); + PolynomialFunction Hk2 = Hk1.polynomialDerivative(); + + PolynomialFunction g0 = new PolynomialFunction(new double[] { 2 * k }); + PolynomialFunction g1 = new PolynomialFunction(new double[] { 0, -2 }); + PolynomialFunction g2 = new PolynomialFunction(new double[] { 1 }); + + PolynomialFunction Hk0g0 = Hk0.multiply(g0); + PolynomialFunction Hk1g1 = Hk1.multiply(g1); + PolynomialFunction Hk2g2 = Hk2.multiply(g2); + + checkNullPolynomial(Hk0g0.add(Hk1g1.add(Hk2g2))); + + } + } + + public void testFirstLaguerrePolynomials() { + + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(3), 6l, "6.0 - 18.0 x + 9.0 x^2 - x^3"); + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(2), 2l, "2.0 - 4.0 x + x^2"); + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(1), 1l, "1.0 - x"); + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(0), 1l, "1.0"); + + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(7), 5040l, + "5040.0 - 35280.0 x + 52920.0 x^2 - 29400.0 x^3" + + " + 7350.0 x^4 - 882.0 x^5 + 49.0 x^6 - x^7"); + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(6), 720l, + "720.0 - 4320.0 x + 5400.0 x^2 - 2400.0 x^3 + 450.0 x^4" + + " - 36.0 x^5 + x^6"); + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(5), 120l, + "120.0 - 600.0 x + 600.0 x^2 - 200.0 x^3 + 25.0 x^4 - x^5"); + checkPolynomial(PolynomialsUtils.createLaguerrePolynomial(4), 24l, + "24.0 - 96.0 x + 72.0 x^2 - 16.0 x^3 + x^4"); + + } + + public void testLaguerreDifferentials() { + for (int k = 0; k < 12; ++k) { + + PolynomialFunction Lk0 = PolynomialsUtils.createLaguerrePolynomial(k); + PolynomialFunction Lk1 = Lk0.polynomialDerivative(); + PolynomialFunction Lk2 = Lk1.polynomialDerivative(); + + PolynomialFunction g0 = new PolynomialFunction(new double[] { k }); + PolynomialFunction g1 = new PolynomialFunction(new double[] { 1, -1 }); + PolynomialFunction g2 = new PolynomialFunction(new double[] { 0, 1 }); + + PolynomialFunction Lk0g0 = Lk0.multiply(g0); + PolynomialFunction Lk1g1 = Lk1.multiply(g1); + PolynomialFunction Lk2g2 = Lk2.multiply(g2); + + checkNullPolynomial(Lk0g0.add(Lk1g1.add(Lk2g2))); + + } + } + + public void testFirstLegendrePolynomials() { + + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(3), 2l, "-3.0 x + 5.0 x^3"); + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(2), 2l, "-1.0 + 3.0 x^2"); + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(1), 1l, "x"); + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(0), 1l, "1.0"); + + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(7), 16l, "-35.0 x + 315.0 x^3 - 693.0 x^5 + 429.0 x^7"); + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(6), 16l, "-5.0 + 105.0 x^2 - 315.0 x^4 + 231.0 x^6"); + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(5), 8l, "15.0 x - 70.0 x^3 + 63.0 x^5"); + checkPolynomial(PolynomialsUtils.createLegendrePolynomial(4), 8l, "3.0 - 30.0 x^2 + 35.0 x^4"); + + } + + public void testLegendreDifferentials() { + for (int k = 0; k < 12; ++k) { + + PolynomialFunction Pk0 = PolynomialsUtils.createLegendrePolynomial(k); + PolynomialFunction Pk1 = Pk0.polynomialDerivative(); + PolynomialFunction Pk2 = Pk1.polynomialDerivative(); + + PolynomialFunction g0 = new PolynomialFunction(new double[] { k * (k + 1) }); + PolynomialFunction g1 = new PolynomialFunction(new double[] { 0, -2 }); + PolynomialFunction g2 = new PolynomialFunction(new double[] { 1, 0, -1 }); + + PolynomialFunction Pk0g0 = Pk0.multiply(g0); + PolynomialFunction Pk1g1 = Pk1.multiply(g1); + PolynomialFunction Pk2g2 = Pk2.multiply(g2); + + checkNullPolynomial(Pk0g0.add(Pk1g1.add(Pk2g2))); + + } + } + + public void testHighDegreeLegendre() { + try { + PolynomialsUtils.createLegendrePolynomial(40); + fail("an exception should have been thrown"); + } catch (ArithmeticException ae) { + // expected + } +// checkPolynomial(PolynomialsUtils.createLegendrePolynomial(40), 274877906944l, +// "34461632205.0" +// + " - 28258538408100.0 x^2" +// + " + 3847870979902950.0 x^4" +// + " - 207785032914759300.0 x^6" +// + " + 5929294332103310025.0 x^8" +// + " - 103301483474866556880.0 x^10" +// + " + 1197358103913226000200.0 x^12" +// + " - 9763073770369381232400.0 x^14" +// + " + 58171647881784229843050.0 x^16" +// + " - 260061484647976556945400.0 x^18" +// + " + 888315281771246239250340.0 x^20" +// + " - 2345767627188139419665400.0 x^22" +// + " + 4819022625419112503443050.0 x^24" +// + " - 7710436200670580005508880.0 x^26" +// + " + 9566652323054238154983240.0 x^28" +// + " - 9104813935044723209570256.0 x^30" +// + " + 6516550296251767619752905.0 x^32" +// + " - 3391858621221953912598660.0 x^34" +// + " + 1211378079007840683070950.0 x^36" +// + " - 265365894974690562152100.0 x^38" +// + " + 26876802183334044115405.0 x^40"); + } + + private void checkPolynomial(PolynomialFunction p, long denominator, String reference) { + PolynomialFunction q = new PolynomialFunction(new double[] { denominator}); + assertEquals(reference, p.multiply(q).toString()); + } + + private void checkPolynomial(PolynomialFunction p, String reference) { + assertEquals(reference, p.toString()); + } + + private void checkNullPolynomial(PolynomialFunction p) { + for (double coefficient : p.getCoefficients()) { + assertEquals(0.0, coefficient, 1.0e-13); + } + } + +} Propchange: commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/polynomials/PolynomialsUtilsTest.java ------------------------------------------------------------------------------ svn:eol-style = native Propchange: commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/polynomials/PolynomialsUtilsTest.java ------------------------------------------------------------------------------ svn:keywords = Author Date Id Revision