NARG GP stacks code

Linked from NARG.

Code by User:obscurite for Brad's GP workshop. This code generates random "programs". This will be further modified to produce programs with desired traits and then to have them evolve. Written for python 3.0.

from random import choice
from random import randint

programList = []           # hold program elements (ints and operations)
opStack = []               # temporarily hold operations as we handle them
intStack = []              # hold ints as we handle them
ops = ['add', 'mul']       # all possible operations


########################################################################
# Stack stuff
def popOp():               # pop operation from op stack
  return opStack.pop()

def pushOp(op):            # push operation onto op stack
  opStack.append(op)

def popProg():             # pop thing from programList
  return programList.pop()

def pushProg(stuff):       # push thing onto programList
  programList.append(stuff)

def popInt():              # pop int from int stack
  return intStack.pop()

def pushInt(stuff):        # push int onto int stack
  intStack.append(stuff)

########################################################################
# Random stuff
def randOp():              # return a random choice of op (add/mul)
  return choice(ops)

def randNum():             # return a random int from 0 to 10
  return randint(0, 10)

def randThing():           # return a random int or random op randomly
  if randint(0, 1):
    return randNum()
  else:
    return randOp()

########################################################################
# main function

def main():

  numthings = 100 # num of things to generate

  # build up a random list of things (ops and ints)
  for i in range(1, numthings):
    pushProg(randThing())      # push a random thing into programList

  # Show what's in the full programList
  print("PROGRAM LIST:")
  print(programList)

  # For every thing in programList, handle it appropriately
  for i in range(1, numthings):
    thing = popProg()
    if isinstance(thing, int): # it's a number, push it to number stack!
      pushInt(thing)
    else:                      # it's an op, do something with numbers!
      if len(intStack) > 1:    # we have at least two ints on num stack
        if (thing == 'mul'):
          pushInt(popInt() * popInt())   # do the mul operation and push
        else:
          pushInt(popInt() + popInt())   # do the add operation and push

  # Show what's left in our op and int stacks
  print("OP STACK:")
  print(opStack)
  print("INT STACK:")
  print(intStack)


########################################################################
# run the program!
main();