[MATH-1234] Impossible NotStrictlyPositiveException after getStandardDeviation()

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 3.2
• Fix Version/s: 3.5

Environment

Windows 7, Java 1.8

• Assignee: Unassigned
• Reporter: Sergii Nechuiviter
• Created: 17/Jun/15 13:32
• Updated: 19/Jun/15 21:42
• Resolved: 19/Jun/15 08:21

Description

org.apache.commons.math3.random.EmpiricalDistribution.density() calls
EmpiricalDistribution.getKernel which calls
bStats.getStandardDeviation() – bStats is SummaryStatistics
and return result caused NotStrictlyPositiveException: standard deviation (0)
in new NormalDistribution(randomData.getRandomGenerator(),
bStats.getMean(), bStats.getStandardDeviation(),
NormalDistribution.DEFAULT_INVERSE_ABSOLUTE_ACCURACY);

As I understand, it shouldn't be so by contract of SummaryStatistics.

Issue Links

• duplicates: MATH-1203 getKernel fails for buckets with only multiple instances of the same value in random.EmpiricalDistribution