Fix overflow issue with large matrices (fixes shogun-toolbox#4595)

karlnapf · May 2, 2019 · 3c9c24e · 3c9c24e
1 parent ac8873a
commit 3c9c24e
Showing 1 changed file with 4 additions and 3 deletions.
diff --git a/src/shogun/statistical_testing/internals/mmd/ComputeMMD.h b/src/shogun/statistical_testing/internals/mmd/ComputeMMD.h
@@ -112,9 +112,10 @@ struct ComputeMMD
 		terms.diag[1]=b_y.diagonal().sum();
 		terms.diag[2]=b_xy.diagonal().sum();
 
-		terms.term[0]=(b_x.sum()-terms.diag[0])/2+terms.diag[0];
-		terms.term[1]=(b_y.sum()-terms.diag[1])/2+terms.diag[1];
-		terms.term[2]=b_xy.sum();
+		// cast to 64 bit to avoid overflows
+		terms.term[0]=(b_x. template cast<float64_t>().sum()-terms.diag[0])/2+terms.diag[0];
+		terms.term[1]=(b_y. template cast<float64_t>().sum()-terms.diag[1])/2+terms.diag[1];
+		terms.term[2]=b_xy. template cast<float64_t>().sum();
 
 		return compute(terms);
 	}