Python - "Local x variable referenced before assignment"

Question

I'm having a problem with my python program and I've spent too many time trying to fix it but I can't. I was hoping you could help me.

Anyway, the problem is in:

def choose_winnerPvsP(p1,p2):

When I run it the part of Player vs Computer woks perfectly, but the part of Player vs Player gives me this error: "Local variable player_1score referenced before assignment" I can't understand why the if's are never checked.

PS: I'm a beginner and I know that the code could be more compact, but for now I just want this thing working. Thanks in advance

#!/usr/bin/env python
# -*- coding: UTF-8 -*-

from random import *
from time import sleep
import sys
import os

os.system("cls") #ou "clear" se estiver em linux

print "******Welcome to Rock Paper Scissors Game!******\n"

playerOrComputer = str(raw_input("Would you like to play against a friend or a computer?(F or C) \n" ))

p1_score = 0
p2_score = 0

def player_turn(nome_player):
    print "What do you want to do, " + nome_player + "?"
    pchoice = str(raw_input("ROCK (R) PAPER (P) SCISSORS (S) or Quit\n>> "))
    if pchoice == "R" or pchoice == "r":
        print "You chosed ROCK"
    elif pchoice == "P" or pchoice == "p":
        print "You chosed PAPER"
    elif pchoice == "S" or pchoice == "s":
        print "You chosed SCISSORS"
    elif pchoice == "quit" or pchoice == "Quit":
        sys.exit()
    else:
        print "I didn't understand! Please repeat."
        player_turn()
    return pchoice

def player_turn2p(nome_player1,p2):
    print "What do you want to do, " + nome_player1 + "?"
    pchoice1 = str(raw_input("ROCK (R) PAPER (P) SCISSORS (S)\n>> "))
    if pchoice1 == "R" or pchoice1 == "r":
        pchoice1 = "ROCK"
        print "You chosed ROCK"
        sleep(1)
        os.system("cls")
    elif pchoice1 == "P" or pchoice1 == "p":
        pchoice1 = "PAPER"
        print "You chosed PAPER"
        sleep(1)
        os.system("cls")
    elif pchoice1 == "S" or pchoice1 == "s":
        pchoice1 = "SCISSORS"
        print "You chosed SCISSORS" 
        sleep(1)
        os.system("cls")
    elif pchoice1 == "quit" or pchoice == "Quit":
        sys.exit()
    else:
        print "I didn't understand!"
        player_turn2p(nome_player1,p2)
    print "What do you want to do, " + p2 + "?"
    pchoice2 = str(raw_input("ROCK (R) PAPER (P) SCISSORS (S)\n>> "))
    if pchoice2 == "R" or pchoice2 == "r":
        print p2 + " chosed ROCK\n" + nome_player1 + " chosed " + pchoice1
    elif pchoice2 == "P" or pchoice2 == "p":
        print p2 + " chosed PAPER\n" + nome_player1 + " chosed " + pchoice1
    elif pchoice2 == "S" or pchoice2 == "s":
        print p2 + " chosed SCISSORS\n" + nome_player1 + " chosed " + pchoice1
    elif pchoice1 == "quit" or pchoice == "Quit":
        sys.exit()
    else:
        print "I didn't understand!"
        player_turn2p(nome_player1,p2)
    return pchoice1, pchoice2

def computer_turn():
    choicecomp = randint(1,3)
    if choicecomp == 1:
        choicecomp = "ROCK"
    elif choicecomp == 2:
        choicecomp = "PAPER"
    elif choicecomp == 3:
        choicecomp = "SCISSORS"
    return choicecomp
    #1-Rock 2-Paper 3-Scissors

def choose_winnerPvsP(p1,p2):
    player_choice1, player_choice2= player_turn2p(p1,p2)
    if player_choice1 == "R" and player_choice2 == "R" or player_choice1 == "r" and player_choice2 == "r" or player_choice1 == "R" and player_choice2 == "r" or player_choice1 == "r" and player_choice2 == "R":
        player_1score = "lose"
        player_2score = "win"
        print "******It's a draw!******"
    elif player_choice1 == "R" and player_choice2 == "P" or player_choice1 == "r" and player_choice2 == "p" or player_choice1 == "R" and player_choice2 == "p" or player_choice1 == "r" and player_choice2 == "P":
        player_1score = "lose"
        player_2score = "win"
        print "******" + p2 + " wins!******"
    elif player_choice1 == "R" and player_choice2 == "S" or player_choice1 == "r" and player_choice2 == "s" or player_choice1 == "R" and player_choice2 == "s" or player_choice1 == "r" and player_choice2 == "S":
        player_1score = "win"
        player_2score = "lose"
        print "******" + p1 + " wins!******"
    elif player_choice1 == "P" and player_choice2 == "R" or player_choice1 == "p" and player_choice2 == "r" or player_choice1 == "P" and player_choice2 == "r" or player_choice1 == "p" and player_choice2 == "R":
        player_1score = "win"
        player_2score = "lose"
        print "******" + p1 + " wins!******"
    elif player_choice1 == "P" and player_choice2 == "P" or player_choice1 == "p" and player_choice2 == "p" or player_choice1 == "P" and player_choice2 == "p" or player_choice1 == "p" and player_choice2 == "P":    
        player_1score = "draw"
        player_2score = "draw"
        print "******It's a draw!******"
    elif player_choice1 == "P" and player_choice2 == "S" or player_choice1 == "p" and player_choice2 == "s" or player_choice1 == "P" and player_choice2 == "s" or player_choice1 == "p" and player_choice2 == "S":
        player_1score = "lose"
        player_2score = "win"
        print "******" + p2 + " wins!******"
    elif player_choice1 == "S" and player_choice2 == "R" or player_choice1 == "s" and player_choice2 == "r" or player_choice1 == "S" and player_choice2 == "r" or player_choice1 == "s" and player_choice2 == "R":
        player_1score = "lose"
        player_2score = "win"
        print "******" + p2 + " wins!******"
    elif player_choice1 == "S" and player_choice2 == "P" or player_choice1 == "s" and player_choice2 == "p" or player_choice1 == "S" and player_choice2 == "p" or player_choice1 == "s" and player_choice2 == "P":
        player_1score = "win"
        player_2score = "lose"
        print "******" + p1 + " wins!******"
    elif player_choice1 == "S" and player_choice2 == "S" or player_choice1 == "s" and player_choice2 == "s" or player_choice1 == "S" and player_choice2 == "s" or player_choice1 == "s" and player_choice2 == "S":
        player_1score = "draw"
        player_2score = "draw"
        print "******It's a draw!******"
    return player_1score, player_2score

def choose_winnerPvsC(player_name,player_choice, computer_choice):

    if player_choice == "R" and computer_choice == "ROCK" or player_choice == "r" and computer_choice == "ROCK":
        computer_score = "draw"
        player_score = "draw"
        print "******It's a draw!****** "
    elif player_choice == "R" and computer_choice == "PAPER" or player_choice == "r" and computer_choice == "PAPER":
        computer_score = "win"
        player_score = "lose"
        print "******I win!****** " 
    elif player_choice == "R" and computer_choice == "SCISSORS" or player_choice == "r" and computer_choice == "SCISSORS":
        player_score = "win"
        computer_score = "lose"
        print "******" + player_name + " wins!****** "
    elif player_choice == "P" and computer_choice == "ROCK" or player_choice == "p" and computer_choice == "ROCK":
        player_score = "win"
        computer_score = "lose"
        print "******" + player_name + " wins!****** "
    elif player_choice == "P" and computer_choice == "PAPER" or player_choice == "p" and computer_choice == "PAPER":    
        computer_score = "draw"
        player_score = "draw"
        print "******It's a draw!******"
    elif player_choice == "P" and computer_choice == "SCISSORS" or player_choice == "p" and computer_choice == "SCISSORS":
        computer_score = "win"
        player_score = "lose"
        print "******I win!****** "
    elif player_choice == "S" and computer_choice == "ROCK" or player_choice == "s" and computer_choice == "ROCK":
        computer_score = "win"
        player_score = "lose"
        print "******I win!****** "
    elif player_choice == "S" and computer_choice == "PAPER" or player_choice == "s" and computer_choice == "PAPER":
        player_score = "win"
        computer_score = "lose"
        print "******" + player_name + " wins!****** "
    elif player_choice == "S" and computer_choice == "SCISSORS" or player_choice == "s" and computer_choice == "SCISSORS":
        computer_score = "draw"
        player_score = "draw"
        print "******It's a draw!****** "
    return player_score, computer_score

def loopPvsP():
    p1score = 0           
    p2score = 0       
    while True:
        player_1score, player_2score = choose_winnerPvsP(p1,p2)
        if player_1score == "win":
            p1score += 1
        elif player_2score == "win":
            p2score += 1
        print p1 + ":",p1score
        print p2 + ":",p2score
        if p1score == 5:
            print "-+-+-+-+-"+ p1.upper() + "IS THE BIG WINNER!!-+-+-+-+-"
            break
        elif p2score == 5:
            print "-+-+-+-+-"+ p2.upper() + "IS THE BIG WINNER!!-+-+-+-+-"
            break       

def loopPvsC():
    pscore = 0
    cscore = 0
    while True:
        pchoice = player_turn(p1c)
        choicecomp = computer_turn()
        print "I chosed "+ choicecomp + "!"
        player_score, computer_score = choose_winnerPvsC(p1c,pchoice, choicecomp)
        if computer_score == "win":
            cscore += 1
        elif player_score == "win":
            pscore += 1
        print "Computer:",cscore
        print p1c + ":",pscore
        if pscore == 5:
            print "-+-+-+-+-YOU ARE THE BIG WINNER!!-+-+-+-+-"
            break
        elif cscore == 5:
            print "-+-+-+-+-I'M THE BIG WINNER!!-+-+-+-+-"
            break

if playerOrComputer == "f" or playerOrComputer == "F":
    p1 = str(raw_input("Player 1: "))
    p2 = str(raw_input("Player 2: "))
    os.system("cls")
    loopPvsP()

elif playerOrComputer == "c" or playerOrComputer == "C":
    p1c = str(raw_input("Player: "))
    os.system("cls")
    loopPvsC()

else:
    print "That's not what I asked!"

Use a debugger, so you will know why the `if` contents are not being executed. — BartoszKP, Aug 22 '15 at 12:04
I'm sorry but I don't know how to work with a debugger. But thanks for the answer. I will see what I can do. — João Pinhal, Aug 22 '15 at 12:07
Then this sounds like the perfect time to learn how to do so, unless of course you wish to pose all your debugging problems as SO questions. You could start by reading [this excellent article by Eric Lippert about debugging small programs such as yours.](http://ericlippert.com/2014/03/05/how-to-debug-small-programs/). — Bart van Nierop, Aug 22 '15 at 12:17
@JoãoPinhal Using a debugger is essential in learning programming. You won't learn anything if you'll ask others to solve such problems for you. — BartoszKP, Aug 22 '15 at 12:24
It looks like all the if clauses are not being met, so the local variables for score are not being initialized. — karthikr, Aug 22 '15 at 12:52
Yes I'm aware of that, but why are the if clauses not being met? — João Pinhal, Aug 22 '15 at 14:19

score 0 · Accepted Answer · answered Aug 22 '15 at 15:28

Meh. Debuggers are overrated -- I go years without using one in Python. Just add a final else clause to your big if/elif statement:

else:
    print "Did not find answer"
    print repr(player_choice), repr(computer_choice)

If that doesn't hit, then it means you have a typo somewhere else, perhaps. Anyway, you can certainly add more debugging statements -- one to each elif clause, if need be.

Which brings up another point -- you have a lot of if/elif clauses.

You might want to investigate things like dicts with values you can add together, or functions you can call, to reduce the number of if/else statements you need.

"dicts" is shorthand for "dictionaries" -- key/value mapping objects — Patrick Maupin, Aug 22 '15 at 20:19

Python - "Local x variable referenced before assignment"

1 Answers1