KrzysztofCiba

#!/bin/env python
""" 
Solves a problem of getting permutation of a given index, 
while you know that permutations are created in a lexicographical order. 
As input you are specifying a list of elements and index of permutation you want to get.
"""

## imports 
from math import factorial
## this one just for checking

KrzysztofCiba

########################################################################
# $HeadURL $
# File: TypedList.py
# Author: Krzysztof.Ciba@NOSPAMgmail.com
# Date: 2012/07/19 08:21:16
########################################################################
""" :mod: TypedList
=======================
.. module: TypedList
:synopsis: typed list

KrzysztofCiba

########################################################################
# $HeadURL $
# File: Observer.py
# Author: Krzysztof.Ciba@NOSPAMgmail.com
# Date: 2012/09/26 09:39:58
########################################################################
""" :mod: Observer 
    ============== 
    .. module: Observer
    :synopsis: Observer pattern  

KrzysztofCiba

#!/usr/bin/env python
import random
import sys

class node( object ):
  """ a vertex
  """
  def __init__( self, key ):
    """ c'tor """
    self.key = key 

KrzysztofCiba

class Node( object ):
  """
  .. class:: Node
  
  rbTree Node
  """

  def __init__( self, key ):
    """  c'tor """
    self.left = None 

KrzysztofCiba

__bc16b = [ 0 ] * (256*256)
for i in range(256*256):
  __bc16b[i] = ( i & 1 ) + __bc16b[i/2]


def popcnt16b( arg ):
  """ popcnt using 16bits loom up table """
  return sum( [ __bc16b[( arg >> i ) & 65535 ] for i in range( 0, arg.bit_length(), 16 ) ] )

KrzysztofCiba

## bit count look up table in range 0..255
__bcLUT = [ 0 ] * 256
for i in range(256):
  __bcLUT[i] = ( i & 1 ) + __bcLUT[i/2]

def popcntLUT( arg ):
  """ popcnt using look up table """
  assert type(arg) in ( int, long )
  return sum( [ __bcLUT[ ( arg >> i ) & 255 ] 
                for i in range( 0, arg.bit_length(), 8 ) ] )

KrzysztofCiba

# --- testBK.py
import sys
import random
from popcnt import popcntBK
up = 2**256
for i in range(1, 1001):
  if not i % 10:
    print ".",
    sys.stdout.flush()
  if not i % 100:

KrzysztofCiba

#!/bin/env python
""" :mod: popcnt
    ============
 
    .. module: popcnt
    :synopsis: couting bits set ("1") in int or long
    .. moduleauthor:: Krzysztof.Ciba@NOSPAMgmail.com    
"""
## bit count look up table in range 0..255
__bcLUT = [ 0 ] * 256

KrzysztofCiba

from multiprocessing import Process, Manager

def sender( S ):
  print "sending 256 MB"
  S["foo"] = "."*256*1024*1024

if __name__ == '__main__':

  m = Manager()
  S = m.dict()