dahawkeyecaller:

It should have been a great party at Pukkelpop Festival, Belgium. The Foo Fighters were present, which made me regret not having bought tickets. I guess I should be happy now that I didn’t. Extreme weather slammed the festival grounds. Today there are 5 dead and counting, with 40 or more people…

>>> class Dummy(object):
...     def __init__(self, n):
...         self.n = n
...         
...     
... 
>>> def f(n):
...     sign = 1
...     for d in set(Dummy(i) for i in xrange(n)):
...         yield d.n * sign
...         sign *= -1
...         
...     
... 
>>> print set(sum(f(10)) for i in xrange(100))
set([-7, -3, 7])
>>> 

Reading the Riots

Entities, Relationships, and Semantics: the State of Structured Search

A nice illustration of possible world semantics.