I have the following code:
#AON = Amount of Numbers to average
def general():
print "Enter how many numbers you will enter."
print "Maximum amount is 10: "
aon = raw_input()
try:
aon = int(aon)
if aon >= 10:
print "I cannot average more than 10 numbers."
general()
else:
start_average()
except ValueError:
print "You entered an invalid input, try again."
general()
def start_average():
if aon == 1:
print "You cannot average one number."
general()
elif aon == 2:
def first_number():
print "First number: "
first_ni = raw_input()
second_number()
first_number()
def second_number():
print "Second number: "
second_ni = raw_input()
ans_two = first_ni / second_ni
second_number()
final_two()
elif aon == 3:
def third_number():
first_number()
second_number()
print "Third number: "
third_ni = raw_input()
ans_three = ans_two / third_ni
third_number()
final_three()
elif aon == 4:
def fourth_number():
first_number()
second_number()
third_number()
print "Fourth number: "
fourth_ni = raw_input()
ans_four = ans_three / fourth_ni
fourth_number()
final_four()
elif aon == 5:
def fifth_number():
first_number()
second_number()
third_number()
fourth_number()
print "Fifth number: "
fifth_ni = raw_input()
ans_five = ans_four / fifth_ni
fifth_number()
final_five
def final_two():
final_input = ans_two
final_answer()
def final_three():
final_input = ans_three
final_answer()
def final_four():
final_input = ans_four
final_answer
def final_five():
final_input = ans_five
final_answer()
def final_six():
final_input = ans_six
final_answer()
def final_seven():
final_input = ans_seven
final_answer()
def final_eight():
final_input = ans_eight
final_answer()
def final_nine():
final_input = ans_nine
final_answer()
def final_answer():
listofnumbers = [first_ni, second_ni, third_ni, fourth_ni, fifth_ni, sixth_ni, seventh_ni, eight_ni, ninth_ni]
print "The average of your numbers:"
print listofnumbers
print "Is = %d." % final_input
general()
It's purpose is to find the average of a number, but when I run it through PowerShell, I get the following error:
Traceback (most recent call last):
File "average.py", line 97, in <module>
general()
File "average.py", line 10, in general
general()
File "average.py", line 10, in general
general()
File "average.py", line 12, in general
start_average()
UnboundLocalError: local variable 'start_average' referenced before assignment
I've probably done this more throughout my code, and I just made this, but I just don't know how to fix it or what is the error showing! I don't understand.
It's hard to tell from what you've pasted, because you've clearly broken the indentation.
But it looks like this code:
print "Enter how many numbers you will enter."
print "Maximum amount is 10: "
… is meant to be inside general, while this code:
aon = raw_input()
try:
aon = int(aon)
if aon >= 10:
print "I cannot average more than 10 numbers."
general()
else:
start_average()
except ValueError:
print "You entered an invalid input, try again."
general()
… is meant to be at module level.
Code is executed in the order it appears. Function definitions are just code, like anything else. So, you can't call a function before you define it, because the function doesn't exist yet.
You're probably about to object, with an example like this:
def foo():
bar()
def bar():
print('Hi!')
foo()
It looks like we're calling bar before it exists, and yet it works. How?
Well, the definition of foo is being executed before bar exists, but that's fine. That just defines a function that will, when run, call whatever bar means. As long as we've defined bar before we call it—and we have—everything is fine.
However, you have a number of similar problems in your code. For example, let's look at this part:
elif aon == 2:
def first_number():
print "First number: "
first_ni = raw_input()
second_number()
first_number()
def second_number():
print "Second number: "
second_ni = raw_input()
ans_two = first_ni / second_ni
second_number()
final_two()
That first_ni is a local variable within the first_number function. Every time you call first_number, a new first_ni gets defined, but only visible within that function. You can't use it in second_number, because second_number can only see its own local variables, and global variables, and first_ni is neither.
The concept you need to understand is called scope. Python has some nice tools to help you understand scope. You can print out locals() and globals() and dir() at any part of your program to see what's in scope there. But you'll need to read the tutorial first.
Indentation and a few other things are questionable. I'm not sure why you're defining all of these functions inside of other functions... I think this will do what you want. You're going to need a lot more error checking though (making sure the inputs are integers, divide by 0, etc.)
>>> def getMean(maxNumsToDivide):
... listNums = []
... for i in range(maxNumsToDivide):
... num = raw_input("Please enter a number: ")
... if not num:
... break
... listNums.append(int(num))
... return float(sum(listNums))/len(listNums)
...
>>> getMean(100)
Please enter a number: 2
Please enter a number: 3
Please enter a number: 4
Please enter a number: 5
Please enter a number: 3
Please enter a number:
3.4
Related
In my python program, I have multiple functions defined, then a main function that also holds the menu. The menu is the first thing that should be displayed, but the program is attempting to run the defined functions that are before the main function, first. This is resulting in many problems. Any suggestions.
#!usr/bin/env python
import operator
saved_string = ''
def remove_letter():
return
def num_compare():
return
def print_string():
print saved_string
return
def calculator():
sign_dict = {"+": operator.add(), "-": operator.sub(), "*": operator.mul(), "&": operator.div()}
num1 = int(raw_input("First number: "))
sign = str(raw_input("Action: "))
num2 = int(raw_input("Second number: "))
print sign_dict[sign] (num1, num2)
return
def accept_store():
global saved_string
saved_string = str(raw_input("Enter string: "))
return
def main():
opt_list = [accept_store(),
calculator(),
print_string(),
num_compare(),
remove_letter()]
while(True):
print "SELLECT OPTIONS:"
print "1\tAccept and Store"
print "2\tCalculator"
print "3\tPrint String"
print "4\tNumber Compare"
print "5\tRemove Letter"
opt_choice = int(raw_input("SELLECTION: "))
opt_choice -= 1
opt_list[opt_choice]()
return
main()
() is a function call notation. So in opt_list, you're listing all the function calls, not the function names. You'd have to change it to:
opt_list = [fn1, fn2, ...]
Then call each function like:
for f in opt_list:
f()
Made my very first program for school using a basic calculator program but added a variable, not sure if it should be global or local. It calculates fine, but does not return 'tribble' as a new integer.
tribble = 1
def buy():
x=int(raw_input("How many?"))
return (tribble + x);
def sell():
x=int(raw_input("How many?"))
return (tribble - x);
def breed():
x=int(raw_input("Multiply them by 2"))
return (tribble * x);
def cull():
x=int(raw_input("Kill half your Tribbles"))
return (tribble / x);
print "1: Buy"
print "2: Sell"
print "3: Breed"
print "4: Cull"
print "0: QUIT"
while True:
CHOICE = int(raw_input("What will you do with your Tribbles?"))
if CHOICE == 1:
print "Buying Tribbles"
print buy()
print "You have" + str(tribble) + "Tribbles."
elif CHOICE == 2:
print sell()
print 'Selling Tribbles'
print "You have" + str(tribble) + "Tribbles."
elif CHOICE == 3:
print 'Breeding Tribbles, good luck.'
print breed()
print "You have" + str(tribble) + "Tribbles."
elif CHOICE == 4:
print "You're killing them!!"
print cull()
print "You have" + str(tribble) + "Tribbles."
elif CHOICE == 0:
exit()
Are you trying to update the value of tribble?
Then instead of print buy() you should update your variable by using: tribble = buy()
That way you know the value has been updated into the result from the function buy().
Do the same for other functions as well.
Hope it helps.
You don't update the value of tribbles in your functions and thus every time a function is called tribbles is being treated as 1, it's original value. Instead of returning tribbles * 2, for example, just do tribbles *= 2 and then return tribbles.
Yes 'tribble' does not get updated inside the while loop. Because everytime the function returns updated tribble, you're just printing it.
You may want to update tribble this way:
...
...
tribble= buy()
print tribble
...
....
You never reassign the result of your operation to the tribble. I also recommend that you avoid global variables where possible. For example, I would rewrite your cull function to the following:
def cull(number_of_tribbles):
x=int(raw_input("Kill half your Tribbles"))
return number_of_tribbles / x # No need for the parenthesis or the semicolon
# To use
tribble = cull(tribble)
# No need for explicit str conversion in print
print "You have", tribble, "Tribbles."
As a side note, it is odd that your message is "Kill half your Tribbles" yet you ask the user for input. You should either hard code to return tribbles / 2 or change the message to the user; same goes for breed.
You can also do it this way:
tribble = 1
def buy():
global tribble
x = int(raw_input("How many?"))
tribble = tribble + x;
...
print "1: Buy"
print "2: Sell"
print "3: Breed"
print "4: Cull"
print "0: QUIT"
while True:
CHOICE = int(raw_input("What will you do with your Tribbles?"))
if CHOICE == 1:
print "Buying Tribbles"
print buy()
print "You have " + str(tribble) + " Tribbles."
...
elif CHOICE == 0:
exit()
All other methods should be changed in a similar way.
However, it's recommended to avoid using global variables.
I need to add a validation whilst in a while loop.
However when I use this validation it doesn't work and instead only comes up with the error message saying I haven't used a base 10/an integer when I want it to come up with the validation error message and let the user try again.
I don't know if having it in a while loop makes the validation I use any different, does it?
Also do I need to change this "def inputNumber(message):" to what my input is stored as?
And this "userInput = int(input(message))" to what my input is stored as?
import time
import random
question = 0
score = 0
name = input("What is your full name?")
print ("Hello " + name, "welcome to The Arithmetic Quiz. Use integers to enter the answer!")
time.sleep(2)
operands1 = list(range(2, 12))
operators = ["+","-","x"]
operands2 = list(range(2, 12))
while question < 10:
operand1 = random.choice(operands1)
operand2 = random.choice(operands2)
operator = random.choice(operators)
def inputNumber(message):
while True:
try:
userInput = int(input(message))
except ValueError:
print("Not an integer! Try again.")
continue
else:
return userInput
break
user_answer =int(input('{} {} {} = '.format(operand1, operator, operand2)))
I doubt you want to have your function definitions within a while loop like you're doing here:
while question < 10:
...
def inputNumber(message):
...
Instead, you can define the function outside the loop and call it x number of times from a loop elsewhere. E.g.
def inputNumber(message):
...
return userInput
while question < 10:
# pick random numbers/operators
...
# call inputNumber() with numbers/operators as message. Return user_answer
user_answer = int(inputNumber('{} {} {} = '.format(operand1, operator, operand2)))
# check if the answer is correct
...
# increment question so it doesn't run infinitely
question += 1
#user6104134 has already solved this problem; however, I'd like to provide an answer for anyone else having similar issues.
Try this solution
import random
import time
question = 0
score = 0
def inputnumber(prompt):
while True:
response = raw_input(prompt)
try:
if isinstance(response, int):
return int(response)
else:
print "Not an integer! Try again."
except ValueError:
print "Not an integer! Try again."
name = raw_input("What is your full name? ")
print ("Hello " + name, "welcome to The Arithmetic Quiz. Use integers to enter the answer!")
time.sleep(2)
operands1 = list(range(2, 12))
operators = ["+", "-", "x"]
operands2 = list(range(2, 12))
while question < 10:
operand1 = random.choice(operands1)
operand2 = random.choice(operands2)
operator = random.choice(operators)
user_answer = int(inputnumber('{} {} {} = '.format(operand1, operator, operand2)))
question += 1
Issues
First, you should declare function definitions outside of your script and call the function by identifier 'inputNumber()'
Also notice the slight change in Try/Except, and the PEP 8 Style Guide compliant formatting.
I have been trying to program a maths quiz that both works and is as efficient as possible. Looking over my code I saw I had a lot of integer inputs and that lead to me having the program to ask the question/exit the system if the criteria isn't met, so to help me I thought that it would be useful to create a new function. Here is my attempt:
def prompt_int(prompt=''):
while True:
if status == prompt_int(prompt=''):
val = input(prompt)
if val in (1,2):
return int(val)
return true
elif status != prompt_int(prompt=''):
val = input(prompt)
if val in (1,2,3):
return int(val)
return true
else:
print("Not a valid number, please try again")
However, when I try to implement this function around my code it doesn't work properly as it says that status isn't defined however, when I do define status it goes into a recursion loop. How can I fix this problem?
Here is my original code before i try to implement this function:
import sys
import random
def get_bool_input(prompt=''):
while True:
val = input(prompt).lower()
if val == 'yes':
return True
elif val == 'no':
return False
else:
sys.exit("Not a valid input (yes/no is expected) please try again")
status = input("Are you a teacher or student? Press 1 if you are a student or 2 if you are a teacher")# Im tring to apply the new function here and other places that require integer inputs
if status == "1":
score=0
name=input("What is your name?")
print ("Alright",name,"welcome to your maths quiz."
"Remember to round all answer to 5 decimal places.")
level_of_difficulty = int(input(("What level of difficulty are you working at?\n"
"Press 1 for low, 2 for intermediate "
"or 3 for high\n")))
if level_of_difficulty not in (1,2,3):
sys.exit("That is not a valid level of difficulty, please try again")
if level_of_difficulty == 3:
ops = ['+', '-', '*', '/']
else:
ops = ['+', '-', '*']
for question_num in range(1, 11):
if level_of_difficulty == 1:
number_1 = random.randrange(1, 10)
number_2 = random.randrange(1, 10)
else:
number_1 = random.randrange(1, 20)
number_2 = random.randrange(1, 20)
operation = random.choice(ops)
maths = round(eval(str(number_1) + operation + str(number_2)),5)
print('\nQuestion number: {}'.format(question_num))
print ("The question is",number_1,operation,number_2)
answer = float(input("What is your answer: "))
if answer == maths:
print("Correct")
score = score + 1
else:
print ("Incorrect. The actual answer is",maths)
if score >5:
print("Well done you scored",score,"out of 10")
else:
print("Unfortunately you only scored",score,"out of 10. Better luck next time")
class_number = input("Before your score is saved ,are you in class 1, 2 or 3? Press the matching number")
while class_number not in ("1","2","3"):
print("That is not a valid class, unfortunately your score cannot be saved, please try again")
class_number = input("Before your score is saved ,are you in class 1, 2 or 3? Press the matching number")
else:
filename = (class_number + "txt")
with open(filename, 'a') as f:
f.write("\n" + str(name) + " scored " + str(score) + " on difficulty level " + str(level_of_difficulty))
with open(filename, 'a') as f:
f = open(filename, "r")
lines = [line for line in f if line.strip()]
f.close()
lines.sort()
if get_bool_input("Do you wish to view previous results for your class"):
for line in lines:
print (line)
else:
sys.exit("Thanks for taking part in the quiz, your teacher should discuss your score with you later")
if status == "2":
class_number = input("Which classes scores would you like to see? Press 1 for class 1, 2 for class 2 or 3 for class 3")
if class_number not in (1,2,3):
sys.exit("That is not a valid class")
filename = (class_number + "txt")
with open(filename, 'a') as f:
f = open(filename, "r")
lines = [line for line in f if line.strip()]
f.close()
lines.sort()
for line in lines:
print (line)
Well, just a part:
def prompt_int(prompt=""):
while True:
val = input(prompt)
if val in ("1", "2"):
return int(val), True
Will ask again and again. And return when the user enter "1" or "2"!
But better: "if val in "12":
def prompt_int(prompt=""):
while True:
val = input(prompt)
if val.isdigit():
return int(val)
Hi if you dont want to have valid values send to your you could change your code as the function above.
But you could also change it to do the system exits:
def prompt_int(prompt="", authorized=()):
while True:
val = raw_input(prompt)
if val.isdigit():
if int(val) in authorized:
return int(val)
else:
sys.exit("Bla bla bla too bad")
def prompt_int(prompt=''):
while True:
if status == prompt_int(prompt=''):
This line will look for the name "status" in the global namespace (module's namespace), and raise a NameError if there's no global variable named 'status'.
If there's one, it will then recursively calls prompt_int without any possible termination, resulting theoretically in an endless recursion, but practically (in CPython at least) in a RuntimeError when it will hit the maximum recursion depth.
There are also quite a few other things that won't work as you expect:
val = input(prompt)
if val in (1,2):
In Python 3.x, val will be a string, so it will never compare equal to an int. In Python 2.x, input() is a shortcut for eval(raw_input()), which might return an int, but is also a huge security flaw since it unconditionnally execute untrusted code.
return int(val)
return true
The second return statement will never be executed, obviously, since the function will exit at the first one.
A simpler implementation might look like this:
# rebinds raw_input to input for python < 3
import sys
if sys.version_info.major < 3:
input = raw_input
def prompt_int(prompt='', choices=None):
while True:
val = input(prompt)
try:
val = int(val)
if choices and val not in choices:
raise ValueError("{} is not in {}".format(val, choices))
return val
except (TypeError, ValueError) as e:
print(
"Not a valid number ({}), please try again".format(e)
)
While we're at it, there's room for improvement in other parts of your code. Let's start with this:
def get_bool_input(prompt=''):
while True:
val = input(prompt).lower()
if val == 'yes':
return True
elif val == 'no':
return False
else:
sys.exit("Not a valid input (yes/no is expected) please try again")
First point: your naming is not consistent. If your other function is named prompt_int, this one should be named prompt_bool. Also, you have one function (prompt_int) looping forever and the other one exiting the whole program on invalid input, which is another inconsistency. If you want to allow the user to exit on any prompt, provide an explicit option for it, ie:
def prompt_bool(prompt, quit='Q'):
prompt += " (hit '{}' to exit) : ".format(quit)
while True:
val = input(prompt).strip().upper()
if val == quit:
sys.exit("Goodbye")
elif val == 'yes':
return True
elif val == 'no':
return False
else:
print "Invalid input '{}', please try again".format(val)
Of course you then want to provide the same option in prompt_int(), which leads to a more generic function:
def get_input_or_quit(prompt, quit="Q"):
prompt += " (hit '{}' to exit) : ".format(quit)
val = input(prompt).strip()
if val.upper() == quit:
sys.exit("Goodbye")
return val
def prompt_bool(prompt):
while True:
val = get_input_or_quit(prompt).lower()
if val == 'yes':
return True
elif val == 'no':
return False
else:
print "Invalid input '{}', please try again".format(val)
And of course you also replace the call to input by a call to get_input_or_quit in prompt_int.
We could go on for long - splitting all your code in distinct, self-contained function, writing a "main()" function to drive them (instead of having the "main" part at the top level), and obviously using the operator module instead of eval().
When you come to the 2nd while loop while x == 2: it's still repeating the whole script even though x /= 1 (not if "n"is entered). Let say we enter "y" on the prompt "Is this correct?" shouldn't x become 3 which stops both the first and the 2nd loop?
This is probably obvious but I'm pretty new.
# -*- coding: utf-8 -*-
import time
x = 1
while x == 1:
print "What's your name?"
name = raw_input("Name: ")
print "How old are you?"
age = raw_input("Age: ")
print "So you are %r years old and your name is %r. Is this correct?" % (age, name)
correct = raw_input("(y/n): ")
while x == 2:
if correct == "y":
x = 3 # x = 3 skips all whiles, not working
time.sleep(1)
elif correct == "n":
time.sleep(1)
x = 1 # x = 1 --> 1st while still in action
else:
print "Invalid input \n\t Loading..."
x = 2 # x = 2 --> 2nd while takes over
print "Where do you live?"
time.sleep(0.5)
country = raw_input("Country: ")
time.sleep(0.5)
city = raw_input("City: ")
time.sleep(1)
print " \n Data: \n\t Name: %r \n \t Age: %r \n \t Country: %r \n \t
City: %r " % (name, age, country, city )
In the code you never change the value of your x to 2 so your inner loop while x==2: never runs and you loop infinitely. You need to change the value of x just inside the while x==1: loop for you to even enter the second loop.
The while structure is totally unnecessary, use functions instead and chain them
def ask():
print "What's your name?"
name = raw_input("Name: ")
print "How old are you?"
age = raw_input("Age: ")
return decide(name,age) #<-- Goes to decide
def decide(name,age):
print "So you are %r years old and your name is %r. Is this correct?" % (age, name)
correct = raw_input("(y/n): ")
if correct == "y":
return name,age #<-- process finishes
elif correct == "n":
return ask() #<-- goes back to asking
else:
print "Invalid input"
return decide(name,age) #<--Goes back to wait for a valid input
name, age = ask() #<--Starts the whole process
While I like my other answer better, if you want this code to work with just a slight modification, just bring the definition of correct to the inner loop and as Abdul Fatir say, kick in an x = 2. Anyhow using creating a state machine this way is not recommended.
x = 1
while x == 1:
print "What's your name?"
name = raw_input("Name: ")
print "How old are you?"
age = raw_input("Age: ")
x = 2 #<--Necessary
while x == 2:
print "So you are %r years old and your name is %r. Is this correct?" % (age, name)
correct = raw_input("(y/n): ")
if correct == "y":
x = 3 # x = 3 skips all whiles, not working
time.sleep(1)
elif correct == "n":
time.sleep(1)
x = 1 # x = 1 --> 1st while still in action
else:
print "Invalid input \n\t Loading..."
x = 2 # x = 2 --> 2nd while takes over
I like the solution involving chaining functions, but I also think that you could use some help with your input validation. I really nice tool for this is not in to validate it ahead of time. For instance
def ask():
print "What's your name?"
name = raw_input("Name: ")
print "How old are you?"
age = raw_input("Age: ")
return decide(name,age) #<-- Goes to decide
def decide(name,age):
print "So you are %r years old and your name is %r. Is this correct?" % (age, name)
correct = raw_input("(y/n): ")
while correct not in ["y", "n"]:
correct = raw_input("(y/n): ")
if correct == "y":
return (name,age) #<--process finishes
else
return ask() #<-- goes back to asking
Just to be clear, I ripped a large portion of that code from another answer, but I think that doing it that way is more efficient, and puts all acceptable answers in once place for easy viewing. It would even allow for more complex input validation, and potentially let you use a constant or config file to define available options.