diff options
Diffstat (limited to 'Lib/test/test_tuple.py')
| -rw-r--r-- | Lib/test/test_tuple.py | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/Lib/test/test_tuple.py b/Lib/test/test_tuple.py index a3f40dd..33a6edd 100644 --- a/Lib/test/test_tuple.py +++ b/Lib/test/test_tuple.py @@ -49,9 +49,13 @@ class TupleTest(seq_tests.CommonTest): # should not exhibit cancellation in tuples like (x,(x,y)) # should be distinct from element hashes: hash(x)!=hash((x,)) # This test exercises those cases. - # For a pure random hash and N=50, the expected number of collisions - # is 7.3. Here we allow twice that number. - # Any worse and the hash function is sorely suspect. + # For a pure random hash and N=50, the expected number of occupied + # buckets when tossing 252,600 balls into 2**32 buckets + # is 252,592.6, or about 7.4 expected collisions. The + # standard deviation is 2.73. On a box with 64-bit hash + # codes, no collisions are expected. Here we accept no + # more than 15 collisions. Any worse and the hash function + # is sorely suspect. N=50 base = range(N) |