diff options
Diffstat (limited to 'Lib/test')
| -rw-r--r-- | Lib/test/sortperf.py | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/Lib/test/sortperf.py b/Lib/test/sortperf.py index cd6bbcb..86b38ba 100644 --- a/Lib/test/sortperf.py +++ b/Lib/test/sortperf.py @@ -74,13 +74,14 @@ def tabulate(r): *sort: random data \sort: descending data /sort: ascending data - 3sort: ascending data but with 3 random exchanges + 3sort: ascending, then 3 random exchanges + +sort: ascending, then 10 random at the end ~sort: many duplicates =sort: all equal !sort: worst case scenario """ - cases = ("*sort", "\\sort", "/sort", "3sort", "~sort", "=sort", "!sort") + cases = tuple([ch + "sort" for ch in r"*\/3+~=!"]) fmt = ("%2s %7s" + " %6s"*len(cases)) print fmt % (("i", "2**i") + cases) for i in r: @@ -100,6 +101,11 @@ def tabulate(r): L[i1], L[i2] = L[i2], L[i1] doit(L) # 3sort + # Replace the last 10 with random floats. + if n >= 10: + L[-10:] = [random.random() for dummy in range(10)] + doit(L) # +sort + # Arrange for lots of duplicates. if n > 4: del L[4:] @@ -117,10 +123,7 @@ def tabulate(r): # This one looks like [3, 2, 1, 0, 0, 1, 2, 3]. It was a bad case # for an older implementation of quicksort, which used the median - # of the first, last and middle elements as the pivot. It's still - # a worse-than-average case for samplesort, but on the order of a - # measly 5% worse, not a quadratic-time disaster as it was with - # quicksort. + # of the first, last and middle elements as the pivot. half = n // 2 L = range(half - 1, -1, -1) L.extend(range(half)) |