Author: brentworden
Date: Fri Apr 1 12:45:21 2005
New Revision: 159727
URL: http://svn.apache.org/viewcvs?view=rev&rev=159727
Log:
PR: 34230
Fixed bug in PolynomialSplineFunction to allow evaluation of the function at
the last knot point.
Modified:
jakarta/commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/PolynomialSplineFunction.java
jakarta/commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/SplineInterpolatorTest.java
jakarta/commons/proper/math/trunk/xdocs/changes.xml
Modified:
jakarta/commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/PolynomialSplineFunction.java
URL:
http://svn.apache.org/viewcvs/jakarta/commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/PolynomialSplineFunction.java?view=diff&r1=159726&r2=159727
==============================================================================
---
jakarta/commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/PolynomialSplineFunction.java
(original)
+++
jakarta/commons/proper/math/trunk/src/java/org/apache/commons/math/analysis/PolynomialSplineFunction.java
Fri Apr 1 12:45:21 2005
@@ -36,7 +36,7 @@
* centered on the knot points to compute the spline function values. See
below.
* <p>
* The domain of the polynomial spline function is
- * <code>[smallest knot, largest knot)</code>. Attempts to evaluate the
+ * <code>[smallest knot, largest knot]</code>. Attempts to evaluate the
* function at values outside of this range generate IllegalArgumentExceptions.
* <p>
* The value of the polynomial spline function for an argument <code>x</code>
@@ -44,7 +44,7 @@
* <ol>
* <li>The knot array is searched to find the segment to which <code>x</code>
* belongs. If <code>x</code> is less than the smallest knot point or greater
- * than or equal to the largest one, an <code>IllegalArgumentException</code>
+ * than the largest one, an <code>IllegalArgumentException</code>
* is thrown.</li>
* <li> Let <code>j</code> be the index of the largest knot point that is less
* than or equal to <code>x</code>. The value returned is <br>
@@ -116,7 +116,7 @@
* Compute the value for the function.
* <p>
* Throws FunctionEvaluationException if v is outside of the domain of the
- * function. The domain is [smallest knot, largest knot).
+ * function. The domain is [smallest knot, largest knot].
* <p>
* See [EMAIL PROTECTED] PolynomialSplineFunction} for details on the
algorithm for
* computing the value of the function.
@@ -125,15 +125,21 @@
* @return the value
* @throws FunctionEvaluationException if v is outside of the domain of
* of the spline function (less than the smallest knot point or greater
- * than or equal to the largest knot point)
+ * than the largest knot point)
*/
public double value(double v) throws FunctionEvaluationException {
- if (v < knots[0] || v >= knots[n]) {
+ if (v < knots[0] || v > knots[n]) {
throw new FunctionEvaluationException(v,"Argument outside domain");
}
int i = Arrays.binarySearch(knots, v);
if (i < 0) {
i = -i - 2;
+ }
+ //This will handle the case where v is the last knot value
+ //There are only n-1 polynomials, so if v is the last knot
+ //then we will use the last polynomial to calculate the value.
+ if ( i >= polynomials.length ) {
+ i--;
}
return polynomials[i].value(v - knots[i]);
}
Modified:
jakarta/commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/SplineInterpolatorTest.java
URL:
http://svn.apache.org/viewcvs/jakarta/commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/SplineInterpolatorTest.java?view=diff&r1=159726&r2=159727
==============================================================================
---
jakarta/commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/SplineInterpolatorTest.java
(original)
+++
jakarta/commons/proper/math/trunk/src/test/org/apache/commons/math/analysis/SplineInterpolatorTest.java
Fri Apr 1 12:45:21 2005
@@ -67,7 +67,9 @@
TestUtils.assertEquals(polynomials[1].getCoefficients(), target,
coefficientTolerance);
// Check interpolation
- assertEquals(0.4,f.value(0.4), interpolationTolerance);
+ assertEquals(0.0,f.value(0.0), interpolationTolerance);
+ assertEquals(0.4,f.value(0.4), interpolationTolerance);
+ assertEquals(1.0,f.value(1.0), interpolationTolerance);
}
public void testInterpolateLinearDegenerateThreeSegment()
@@ -88,7 +90,9 @@
TestUtils.assertEquals(polynomials[2].getCoefficients(), target,
coefficientTolerance);
// Check interpolation
- assertEquals(1.4,f.value(1.4), interpolationTolerance);
+ assertEquals(0,f.value(0), interpolationTolerance);
+ assertEquals(1.4,f.value(1.4), interpolationTolerance);
+ assertEquals(1.5,f.value(1.5), interpolationTolerance);
}
public void testInterpolateLinear() throws Exception {
@@ -179,11 +183,11 @@
}
/**
- * verifies that f(x[i]) = y[i] for i = 0..n -1 where n is common length
-- skips last point.
+ * verifies that f(x[i]) = y[i] for i = 0..n-1 where n is common length.
*/
protected void verifyInterpolation(UnivariateRealFunction f, double x[],
double y[])
throws Exception{
- for (int i = 0; i < x.length - 1; i++) {
+ for (int i = 0; i < x.length; i++) {
assertEquals(f.value(x[i]), y[i], knotTolerance);
}
}
Modified: jakarta/commons/proper/math/trunk/xdocs/changes.xml
URL:
http://svn.apache.org/viewcvs/jakarta/commons/proper/math/trunk/xdocs/changes.xml?view=diff&r1=159726&r2=159727
==============================================================================
--- jakarta/commons/proper/math/trunk/xdocs/changes.xml (original)
+++ jakarta/commons/proper/math/trunk/xdocs/changes.xml Fri Apr 1 12:45:21 2005
@@ -39,6 +39,10 @@
<body>
<release version="1.1" date="In Development"
description="Jakarta Commons Math 1.1 - Development">
+ <action dev="brentworden" type="fix" due-to="Ben Litchfield">
+ Fixed bug in PolynomialSplineFunction to allow evaluation of the
+ function at the last knot point.
+ </action>
<action dev="brentworden" type="add">
Added Weibull distribution implementation.
</action>
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