MATH-1462: Extend workaround for bins that contain up to 3 values.
diff --git a/commons-math-legacy/src/main/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistribution.java b/commons-math-legacy/src/main/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistribution.java
index 7929378..cca2c19 100644
--- a/commons-math-legacy/src/main/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistribution.java
+++ b/commons-math-legacy/src/main/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistribution.java
@@ -409,7 +409,8 @@
++i;
}
- final ContinuousDistribution kernel = getKernel(binStats.get(i));
+ final SummaryStatistics stats = binStats.get(i);
+ final ContinuousDistribution kernel = getKernel(stats);
final double kB = kB(i);
final double[] binBounds = getUpperBounds();
final double lower = i == 0 ? min : binBounds[i - 1];
@@ -546,7 +547,7 @@
*/
private static Function<SummaryStatistics, ContinuousDistribution> defaultKernel() {
return stats -> {
- if (stats.getN() <= 1 ||
+ if (stats.getN() <= 3 ||
stats.getVariance() == 0) {
return new ConstantContinuousDistribution(stats.getMean());
} else {
diff --git a/commons-math-legacy/src/test/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistributionTest.java b/commons-math-legacy/src/test/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistributionTest.java
index 4f26e4e..addd94a 100644
--- a/commons-math-legacy/src/test/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistributionTest.java
+++ b/commons-math-legacy/src/test/java/org/apache/commons/math4/legacy/distribution/EmpiricalDistributionTest.java
@@ -489,13 +489,12 @@
6212, 5961, 711
};
- final EmpiricalDistribution ed = EmpiricalDistribution.from(1000, data);
+ final double p = 0.32;
+ for (int i = 745; i <= 1100; i++) {
+ final EmpiricalDistribution ed = EmpiricalDistribution.from(i, data);
+ final double v = ed.inverseCumulativeProbability(p);
- double v;
- double p;
-
- p = 0.32;
- v = ed.inverseCumulativeProbability(p);
- Assert.assertTrue("p=" + p + " => v=" + v, Double.isFinite(v));
+ Assert.assertTrue("p=" + p + " => v=" + v, Double.isFinite(v));
+ }
}
}
diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index 595ebe8..5c276ce 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -97,6 +97,9 @@
nightmare was one of the main reasons for creating more focused
components.]
">
+ <action dev="erans" type="fix" issue="MATH-1462">
+ "EmpiricalDistribution": Use constant kernel for bins that contain up to 3 values.
+ </action>
<action dev="aherbert" due-to="Arturo Bernal" type="update">
Simplify assertions with simpler equivalent.
</action>
