diff --git a/src/ivfkmeans.c b/src/ivfkmeans.c
index ee161c0..c2c18f1 100644
--- a/src/ivfkmeans.c
+++ b/src/ivfkmeans.c
@@ -148,23 +148,25 @@ QuickCenters(Relation index, VectorArray samples, VectorArray centers, IvfflatTy
 	/* Fill remaining with random data */
 	while (centers->length < centers->maxlen)
 	{
+		Datum		center = PointerGetDatum(VectorArrayGet(centers, centers->length));
+
 		if (type == IVFFLAT_TYPE_VECTOR)
 		{
-			Vector	   *vec = (Vector *) VectorArrayGet(centers, centers->length);
+			Vector	   *vec = DatumGetVector(center);
 
 			SET_VARSIZE(vec, VECTOR_SIZE(dimensions));
 			vec->dim = dimensions;
 
 			for (int j = 0; j < dimensions; j++)
 				vec->x[j] = RandomDouble();
-
-			/* Normalize if needed (only needed for random centers) */
-			if (normprocinfo != NULL)
-				ApplyNorm(normprocinfo, collation, PointerGetDatum(vec), type);
 		}
 		else
 			elog(ERROR, "Unsupported type");
 
+		/* Normalize if needed (only needed for random centers) */
+		if (normprocinfo != NULL)
+			ApplyNorm(normprocinfo, collation, center, type);
+
 		centers->length++;
 	}
 }
@@ -434,7 +436,8 @@ ElkanKmeans(Relation index, VectorArray samples, VectorArray centers, IvfflatTyp
 
 		for (int64 j = 0; j < numCenters; j++)
 		{
-			Vector	   *vec = (Vector *) VectorArrayGet(newCenters, j);
+			Datum		center = PointerGetDatum(VectorArrayGet(newCenters, j));
+			Vector	   *vec = DatumGetVector(center);
 
 			if (centerCounts[j] > 0)
 			{
@@ -458,7 +461,7 @@ ElkanKmeans(Relation index, VectorArray samples, VectorArray centers, IvfflatTyp
 
 			/* Normalize if needed */
 			if (normprocinfo != NULL)
-				ApplyNorm(normprocinfo, collation, PointerGetDatum(vec), type);
+				ApplyNorm(normprocinfo, collation, center, type);
 		}
 
 		/* Step 5 */