Minor fix in Math

Summary: $title

Reviewed By: enpe

Differential Revision:
D86107501

Privacy Context Container: L1192943

fbshipit-source-id: 00ed4819ccaec48e331f2a3f224086e4e20ec361

Author: janherling

impl/ocean/math/ClusteringKMeans.h

@@ -253,7 +253,7 @@ class Clustering<false>::Data
 		const Observation** observationPointers_ = nullptr;
 
 		/// The number of observation elements of this data object.
-		size_t numberObservations_;
+		size_t numberObservations_ = 0;
 };
 
 /**