Turing Machine/Program Simulation for ECS631 Assignment

turing_table.py

import sys, argparse
args, res = None, None

def info(tape, n, config):
    """Do shananigans before any computation"""
    if(args.verbose):
        print("Config: %s" % config)
        print("Cursor is at %d" % n)
        print("Tape is ")
    if(args.strings):
        res = ''.join(map(lambda i: str(i), tape))
        print(res)
    else:
        res = tape
        print(res)
    print("=" * len(tape))

def f(tape, n):
    info(tape, n, "f")
    pos = n
    if(tape[pos] == '0' or tape[pos] == '1'):
        pos += 2 # move to the right twice
        f(tape, pos)
    elif(tape[pos] == ''):
        tape[pos] = '0'
        pos -= 2 # move to the left twice
        c(tape, pos)


def p(tape, n):
    info(tape, n, "p")
    pos = n
    if(tape[pos] == 'x'):
        tape[pos] = ''
        pos += 1 # move to the right once
        q(tape, pos)
    elif(tape[pos] == 'e'):
        pos += 1 # move to the right once
        f(tape, pos)
    elif(tape[pos] == ''):
        pos -= 2 # move to the left twice
        p(tape, pos)

def q(tape, n):
    info(tape, n, "q")
    pos = n
    if(tape[pos] == '0' or tape[pos] == '1'):
        pos += 2 # move to the right twice
        q(tape, pos)
    elif(tape[pos] == ''):
        tape[pos] = '1'
        pos -= 1 # move to the left once
        p(tape, pos)

def c(tape, n):
    info(tape, n, "c")
    pos = n
    if(tape[pos] == '1'):
        pos += 1 # move to the right once
        tape[pos] = 'x'
        pos -= 3 # move to the left 3 times
        c(tape, pos)
    elif(tape[pos] == '0'):
        q(tape, pos)

def b(tape, n):
    info(tape, n, "b")
    pos = n
    if tape[pos] == 'e':
        tape[pos] = 'e'
        pos += 1 # move to the right once
        tape[pos] = '0'
        pos += 2 # move to the right twice
        tape[pos] = '0'
        pos -= 2
        c(tape, pos)

def main(args):
    tape, n = ['e'], 0
    for i in range(0, args.tape_length): tape.append('')
    try:
        b(tape, n)
    except IndexError:
        print("Stopped for now")

if __name__ == '__main__':
    parser = argparse.ArgumentParser("A simulation of a turing program computinga sequence")
    parser.add_argument('tape_length', type=int, help='The length of the tape')
    parser.add_argument('-s', '--strings', action='store_true', default=False, help='print strings rather than arrays')
    parser.add_argument('-v', '--verbose', action='store_true', default=False, help='Verbose mode. Print all helpful messages')
    args = parser.parse_args()
    main(args)