- Add a warning about quicksort being stable only with some

operators


git-svn-id: svn://svn.gna.org/svn/sgpemv2/trunk@1066 3ecf2c5c-341e-0410-92b4-d18e462d057c

plugins/pyloader/src/CPUPolicy.py

@@ -109,11 +109,11 @@ class CPUPolicy:
     # @code
     # # As a lambda anonymous function (preferred)
     # # (x and y are two DynamicSchedulable objects)
-    # cmpf = lambda x,y: x.someProperty() < y.someProperty()
+    # cmpf = lambda x,y: x.someProperty() <= y.someProperty()
     #
     # # As a normal *global* function
     # def compare(a,b):
-    #     return a.someProperty < b.someProperty()
+    #     return a.someProperty <= b.someProperty()
     # cmpf = compare
     # @endcode
     #
@@ -124,6 +124,12 @@ class CPUPolicy:
     #     self.sort(queue, cmpf)
     # @endcode
     #
+    # Since queue.sort() uses a in-place version of the 
+    # quicksort algorithm, note the effect of using "<"
+    # instead than "<=": quicksort wouldn't be stable anymore.
+    # You have been warned. If your policy behaves strangely,
+    # this may be the cause.
+    #
     # @param self The object caller
     # @param queue The ReadyQueue to be sorted in place
     # @param cmpf The binary function to use to compare elements