question: private static void probabilisticUnionTest ( final ISchemaVersion schemaVersion ) throws IOException { final Writer output = openOutput ( schemaVersion , "probabilistic_probabilistic" , TestType . UNION ) ; final Random random = new Random ( randomLong ( ) ) ; final HLL hll = newHLL ( HLLType . EMPTY ) ; final HLL emptyHLL = newHLL ( HLLType . EMPTY ) ; cumulativeUnionLine ( output , hll , emptyHLL , schemaVersion ) ; for ( int i = 0 ; i < 1000 ; i ++ ) { final HLL fullHLL = newHLL ( HLLType . FULL ) ; final int elementCount = random . nextInt ( 10000 ) ; for ( int j = 0 ; j < elementCount ; j ++ ) { fullHLL . addRaw ( random . nextLong ( ) ) ; } cumulativeUnionLine ( output , hll , fullHLL , schemaVersion ) ; } output . flush ( ) ; output . close ( ) ; }
target:  Unions an EMPTY accumulator with FULL HLLs, each having many registers set, twice in a row to verify that the set properties are satisfied. Format: cumulative union Tests: - EMPTY U FULL - FULL U FULL