Remove unused cruft from combinations.py

diff --git a/combinations.py b/combinations.py
index 987d6db214158b74e5ac2fbd1551da561593ce7b..50b7bab397d36e98722a7fd8e80f42a5701faacd 100644 (file)
--- a/combinations.py
+++ b/combinations.py
@@ -4,24 +4,6 @@
 from __future__ import generators
 
 
 from __future__ import generators
 
 

-def xcombinations(items, n):
-    """Iterate through ordered, length `n` subsets of `items`.
-
-    >>> for c in xcombinations([1, 2, 3], 2):
-    ...     print c
-    [1, 2]
-    [1, 3]
-    [2, 1]
-    [2, 3]
-    [3, 1]
-    [3, 2]
-    """
-    if n==0: yield []
-    else:
-        for i in xrange(len(items)):
-            for cc in xcombinations(items[:i]+items[i+1:],n-1):
-                yield [items[i]]+cc
-

 def xunique_combinations(items, n):
     """Iterate through unordered, length `n` subsets of `items`.
 
 def xunique_combinations(items, n):
     """Iterate through unordered, length `n` subsets of `items`.
 


@@ -36,39 +18,3 @@ def xunique_combinations(items, n):
         for i in xrange(len(items)):
             for cc in xunique_combinations(items[i+1:],n-1):
                 yield [items[i]]+cc
         for i in xrange(len(items)):
             for cc in xunique_combinations(items[i+1:],n-1):
                 yield [items[i]]+cc

-
-def xselections(items, n):
-    """Iterate through all length `n` multisets of `items`.
-
-    >>> for c in xselections([1, 2, 3], 2):
-    ...     print c
-    [1, 1]
-    [1, 2]
-    [1, 3]
-    [2, 1]
-    [2, 2]
-    [2, 3]
-    [3, 1]
-    [3, 2]
-    [3, 3]
-    """
-    if n==0: yield []
-    else:
-        for i in xrange(len(items)):
-            for ss in xselections(items, n-1):
-                yield [items[i]]+ss
-
-def xpermutations(items):
-    """Iterate through all permutations of `items`.
-
-    >>> for c in xpermutations([1, 2, 3]):
-    ...     print c
-    [1, 2, 3]
-    [1, 3, 2]
-    [2, 1, 3]
-    [2, 3, 1]
-    [3, 1, 2]
-    [3, 2, 1]
-    """
-    return xcombinations(items, len(items))
-