NameError, variable not defined in Python

Question

so the ultimate goal is to run best 2 out of 3 games of rock, paper, scissors, lizard, spock. i haven't added a loop yet or anything like that i'm trying to get the game itself running first but I'm coming across a NameError, it's saying the 'result' variable is undefined.

I've tried returning it but that doesn't appear to be working, but I also maybe don't know what I'm doing?

    
def number_to_name(number):

    if number == 1:
        return 'scissors'
    elif number == 2:
        return 'rock'
    elif number == 3:
        return 'paper'
    elif number == 4:
        return 'lizard'
    elif number == 5:
        return 'spock'
    else:
        print ("Error: Invalid number")

def name_to_number(name):

    if name == 'scissors':
        return 1
    elif name == 'rock':
        return 2
    elif name == 'paper':
        return 3
    elif name == 'lizard':
        return 4
    elif name == 'spock':
        return 5
    else:
        print ("Error: Invalid number")


def rpsls(name):

    player_score, computer_score = (0, 0)
    player_input = name_to_number(name)
    computer_input = random.randint(1,5)
    result = (player_input - computer_input) % 5


if result == 1 or result == 2:
    print("player wins")
    player_score += 1
    print("Player {}, Computer {}". format(player_score, computer_score))
    
elif result == 3 or result == 4:
    game = "computer wins"
    computer_score += 1
    print("Player {}, Computer {}". format(player_score, computer_score))
    
elif result == 0:
    game = "it's a tie"
    print("Player {}, Computer {}". format(player_score, computer_score))
    
else:
    print("error")


        
rpsls("rock")
rpsls("spock")
rpsls("paper")
rpsls("lizard")
rpsls("scissors")

Please reduce and enhance this into the expected MRE. You posted 50 lines of code for a 5-line problem. You apparently didn't try to reduce the code to trace the problem. See this lovely reference for debugging help. — Prune
– Prune, Commented Jun 25, 2020 at 4:47
Your condition is not placed inside the loop..Move to inside the rpsls function — NAGA RAJ S
– NAGA RAJ S, Commented Jun 25, 2020 at 4:50

Shaiful Islam · Accepted Answer · 2020-06-25 04:48:30Z

Your conditions should be inside the rpsls function.Because you result variable is local variable. You can't fetch this variable globally.

> def rpsls(name):
>     player_score, computer_score = (0, 0)
>     player_input = name_to_number(name)
>     computer_input = random.randint(1, 5)
>     result = (player_input - computer_input) % 5
> 
> 
>     if result == 1 or result == 2:
>         print("player wins")
>         player_score += 1
>         print("Player {}, Computer {}".format(player_score, computer_score))
> 
>     elif result == 3 or result == 4:
>         game = "computer wins"
>         computer_score += 1
>         print("Player {}, Computer {}".format(player_score, computer_score))
> 
>     elif result == 0:
>         game = "it's a tie"
>         print("Player {}, Computer {}".format(player_score, computer_score))
> 
>     else:
>         print("error")

Sri Harsha K M · Accepted Answer · 2020-06-25 05:03:01Z

0

Your variable result is inside the function rpsls. So the scope of result lies to the function only.

A easy solution would be assign a 0 value to result before the function 'rpsls' This way your updating a globally defined variable inside the function.

result = 0
def rpsls(name):
   #Your code

The best way would be to write a class, have a class level variable result, and put all this code into the class.

answered Jun 25, 2020 at 5:03

Sri Harsha K M

312 bronze badges

Comments

Red · Accepted Answer · 2020-06-25 04:44:49Z

0

First of all, since result is only defined in the function, it is only accessable inside that specific function, unless you choose to use the global method, which I wouldn't recommend.

Second, since you called result before you called the function that actually defines result, even if you use global, it will still not be defined for that specific line.

answered Jun 25, 2020 at 4:44

Red

27.7k8 gold badges44 silver badges63 bronze badges

Collectives™ on Stack Overflow

NameError, variable not defined in Python

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related