Author: luc
Date: Sat Aug 18 18:09:45 2012
New Revision: 1374630
URL: http://svn.apache.org/viewvc?rev=1374630&view=rev
Log:
Polynomials now implement the new UnivariateDifferentiable interface.
Modified:
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialFunction.java
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialSplineFunction.java
Modified:
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialFunction.java
URL:
http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialFunction.java?rev=1374630&r1=1374629&r2=1374630&view=diff
==============================================================================
---
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialFunction.java
(original)
+++
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialFunction.java
Sat Aug 18 18:09:45 2012
@@ -25,6 +25,8 @@ import org.apache.commons.math3.exceptio
import org.apache.commons.math3.analysis.DifferentiableUnivariateFunction;
import org.apache.commons.math3.analysis.UnivariateFunction;
import org.apache.commons.math3.analysis.ParametricUnivariateFunction;
+import org.apache.commons.math3.analysis.differentiation.DerivativeStructure;
+import
org.apache.commons.math3.analysis.differentiation.UnivariateDifferentiable;
import org.apache.commons.math3.util.FastMath;
import org.apache.commons.math3.util.MathUtils;
@@ -36,7 +38,7 @@ import org.apache.commons.math3.util.Mat
*
* @version $Id$
*/
-public class PolynomialFunction implements DifferentiableUnivariateFunction,
Serializable {
+public class PolynomialFunction implements UnivariateDifferentiable,
DifferentiableUnivariateFunction, Serializable {
/**
* Serialization identifier
*/
@@ -137,6 +139,27 @@ public class PolynomialFunction implemen
return result;
}
+
+ /** {@inheritDoc}
+ * @since 3.1
+ * @throws NoDataException if {@code coefficients} is empty.
+ * @throws NullArgumentException if {@code coefficients} is {@code null}.
+ */
+ public DerivativeStructure value(final DerivativeStructure t)
+ throws NullArgumentException, NoDataException {
+ MathUtils.checkNotNull(coefficients);
+ int n = coefficients.length;
+ if (n == 0) {
+ throw new
NoDataException(LocalizedFormats.EMPTY_POLYNOMIALS_COEFFICIENTS_ARRAY);
+ }
+ DerivativeStructure result =
+ new DerivativeStructure(t.getFreeParameters(), t.getOrder(),
coefficients[n - 1]);
+ for (int j = n - 2; j >= 0; j--) {
+ result = result.multiply(t).add(coefficients[j]);
+ }
+ return result;
+ }
+
/**
* Add a polynomial to the instance.
*
Modified:
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialSplineFunction.java
URL:
http://svn.apache.org/viewvc/commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialSplineFunction.java?rev=1374630&r1=1374629&r2=1374630&view=diff
==============================================================================
---
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialSplineFunction.java
(original)
+++
commons/proper/math/trunk/src/main/java/org/apache/commons/math3/analysis/polynomials/PolynomialSplineFunction.java
Sat Aug 18 18:09:45 2012
@@ -21,6 +21,8 @@ import java.util.Arrays;
import org.apache.commons.math3.util.MathArrays;
import org.apache.commons.math3.analysis.DifferentiableUnivariateFunction;
import org.apache.commons.math3.analysis.UnivariateFunction;
+import org.apache.commons.math3.analysis.differentiation.DerivativeStructure;
+import
org.apache.commons.math3.analysis.differentiation.UnivariateDifferentiable;
import org.apache.commons.math3.exception.OutOfRangeException;
import org.apache.commons.math3.exception.NumberIsTooSmallException;
import org.apache.commons.math3.exception.DimensionMismatchException;
@@ -61,7 +63,7 @@ import org.apache.commons.math3.exceptio
*
* @version $Id$
*/
-public class PolynomialSplineFunction implements
DifferentiableUnivariateFunction {
+public class PolynomialSplineFunction implements UnivariateDifferentiable,
DifferentiableUnivariateFunction {
/**
* Spline segment interval delimiters (knots).
* Size is n + 1 for n segments.
@@ -168,6 +170,28 @@ public class PolynomialSplineFunction im
return new PolynomialSplineFunction(knots, derivativePolynomials);
}
+
+ /** {@inheritDoc}
+ * @since 3.1
+ */
+ public DerivativeStructure value(final DerivativeStructure t) {
+ final double t0 = t.getValue();
+ if (t0 < knots[0] || t0 > knots[n]) {
+ throw new OutOfRangeException(t0, knots[0], knots[n]);
+ }
+ int i = Arrays.binarySearch(knots, t0);
+ if (i < 0) {
+ i = -i - 2;
+ }
+ // This will handle the case where t is the last knot value
+ // There are only n-1 polynomials, so if t is the last knot
+ // then we will use the last polynomial to calculate the value.
+ if ( i >= polynomials.length ) {
+ i--;
+ }
+ return polynomials[i].value(t.subtract(knots[i]));
+ }
+
/**
* Get the number of spline segments.
* It is also the number of polynomials and the number of knot points - 1.
