Develop Reference

Why am I not breaking out of a try loop with a break statement?

My code for now works as desired where the user can input a level 1-3 depending on how hard they would like it to be (1-3 being the amount of digits the numbers will have in the math equation), and then must solve math equations. Those math equations will output EEE if the answer is incorrect and everything works as planned if you correctly answer the question as it exits the function and adds one total_correct_answers variable at the bottom, then will prompt you with another equation. However, if you input an incorrect answer and then a correct answer, you will just be prompted with the same question over and over again without the try loop being truly broken out of and total_correct_answers not being incremented positively by 1. The incrementation block of code is at lines 61-65, and the equation code is lines 30-49.
import random
def main():
ten_questions()
def get_level():
while True:
try:
level_input = int(input("Level: "))
if level_input in [1,2,3]:
return level_input
except:
pass
def integer_generator(level):
if level == 1:
x = random.randint(0,9)
y = random.randint(0,9)
elif level == 2:
x = random.randint(10, 99)
y = random.randint(10, 99)
else:
x = random.randint(100, 999)
y = random.randint(100, 999)
return x, y
def question_generator(x, y):
real_answer = x + y
wrong_counter = 0
while True:
try:
answer_given = input(str(x) + " + " + str(y) + " = ")
if int(answer_given) == real_answer:
if wrong_counter == 0:
return True
elif int(answer_given) == real_answer and wrong_counter != 0:
break
else:
while wrong_counter < 2:
print("EEE")
wrong_counter +=1
break
else:
print(str(x) + " + " + str(y) + " = " + str(real_answer))
print("False, that was last attempt")
break
except:
print("EEE")
pass
def ten_questions():
num_of_questions = 0
total_correct_answers = 1
my_level = get_level()
correct_answers = question_generator(*integer_generator(my_level))
while num_of_questions <= 8:
question_generator(*integer_generator(my_level))
num_of_questions +=1
if correct_answers == True:
total_correct_answers +=1
print("Score: " + str(total_correct_answers))
if __name__ == "__main__":
main()

Because of your line 36:
if int(answer_given) == real_answer: happens when someone answers correctly, wether they are right or wrong. So it enters the if, and then faces if wrong_counter == 0: which discards wrong answers. So just replace those two lines with if int(answer_given) == real_answer and wrong_counter == 0: and you are good to go.

Budget tracker program not working in Linux

I am trying to improve this program. I am working with Linux. I want to add a menu function where the user can pick an option and based on the option call the respective function, but the program is not working, when I run it in the Terminal it doesn't do anything and doesn't show any errors. Please, I need help to solve the problem and make the program works. Thanks!
Here's what I have so far, still there are some functions that need to develop:
#! /usr/bin/python3
import sys
def menu(self):
print ("""
1. Add an Expense
2. Remove an Expense
3. Add revenue
4. Remove Revenue
5. Exit
""")
option = input ("What would you like to do [Number Only]?")
if option == "1":
self.add_expense()
elif option == "2":
self.remove_expense()
elif option == "3":
self.add_revenue()
elif option == "4":
self.remove_revenue()
else:
self.reset_program()
self.close_program()
return option
def add_expense(self):
def __init__(self):
self.month_balance = 0
self.expenses = 0
self.expense_list = []
self.expense_name = []
self.month_balance_name = []
self.month_balance_list = []
self.prompt_income()
def month_balance_ask(self):
add_month_balance = input('Add monthly balance? [y/n]: ')
return add_month_balance
def month_balance_sum(self):
self.month_balance = sum(self.month_balance_list)
def expense_ask(self):
add_expense = input('Add expense? [y/n]: ')
return add_expense
def expense_sum(self):
self.expenses = sum(self.expense_list)
def month_balance_check(self):
if not self.month_balance_list:
print('Please enter at least one monthly balance. ')
self.prompt_month_balance()
def expense_check(self):
if not self.expense_list:
print('Please enter at least one expense. ')
self.prompt_expense()
def prompt_month_balance(self):
x = False
while not x:
result = self.month_balance_ask()
if result == 'y':
month_balance_input = int(input('Enter monthly balance. [Numbers Only]: '))
self.month_balance_list.append(month_balance_input)
month_balance_name = input('Enter monthly balance name. [Name Only]: ')
self.month_balance_name.append(month_balance_name)
else:
self.month_balance_check()
x = True
self.month_balance_sum()
name = [name for name in self.month_balance_name]
month_balance = [month_balance for month_balance in self.month_balance_list]
month_balancedict = dict(zip(name, month_balance))
for k in incomedict:
print(k + ': ', '$' + str(month_balancedict[k]))
print('Total user monthly balance: ', '$' + str(self.month_balance))
self.prompt_expense()
def prompt_expense(self):
x = False
while not x:
result = self.expense_ask()
if result == 'y':
expense_input = int(input('Enter expense amount. [Numbers Only]: '))
self.expense_list.append(expense_input)
expense_name = input('Enter expense name. [Name Only]: ')
self.expense_name.append(expense_name)
else:
self.expense_check()
x = True
self.expense_sum()
name = [name for name in self.expense_name]
expense = [income for income in self.expense_list]
expensedict = dict(zip(name, expense))
for k in expensedict:
print(k + ': ', '$' + str(expensedict[k]))
print('Total user expenses: ', '$' + str(self.expenses))
self.added_expense()
def added_expense(self):
expenseadded = self.month_balance - self.expenses
if expenseadded < 0:
print('You are in the negative, you have a deficit of ' + '$' + str(expenseadded))
if expenseadded == 0:
print('You have broken even, you are spending exactly as much as you make.')
if expenseadded > 0:
print('You are in the positive, you have a surplus of ' + '$' + str(expenseadded))
another = input('Would you like to run another analysis? [y/n]: ')
if another == 'y':
self.menu()
else:
self.reset_program()
self.close_program()
def remove_expense(self):
print("code goes here")
def add_revenue(self):
print("code goes here")
def remove_revenue(self):
print("code goes here")
def reset_program(self):
self.month_balance = 0
self.expenses = 0
del self.expense_list[0:]
del self.expense_name[0:]
del self.month_balance_name[0:]
del self.month_balance_list[0:]
self.prompt_month_balance()
def close_program(self):
print('Exiting Program.')
sys.exit(0)

Menu-driven collection of non-negative integers

I'm attempting to create a menu-driven program where python will accept a collection of non-negative integers. It will calculate the mean and median and display the values on the screen. I want my first option to be "Add a number to the list/array", I want my second option to be "Display the mean", the third to be "Display the median", the fourth "Print the list/array to the screen", the fifth "Print the list/array in reverse order" and the last option "Quit". So far I have gotten:
def main():
myList = [ ]
addOne(myList)
choice = displayMenu()
while choice != '6':
if choice == '1':
addOne(myList)
elif choice == '2':
mean(myList)
elif choice == '3':
median(myList)
elif choice == '4':
print(myList)
elif choice == '5':
print(myList)
choice = displayMenu()
print ("\nThanks for playing!\n\n")
def displayMenu():
myChoice = '0'
while myChoice != '1' and myChoice != '2' \
and myChoice != '3' \
and myChoice != '4' and myChoice != '5':
print("""\n\nPlease choose
1. Add a number to the list/array
2. Display the mean
3. Display the median
4. Print the list/array to the screen
5. Print the list/array in reverse order
6. Quit
""")
myChoice = input("Enter option---> ")
if myChoice != '1' and myChoice != '2' and \
myChoice != '3' and myChoice != '4' and myChoice != '5':
print("Invalid option. Please select again.")
return myChoice
#This should make sure that the user puts in a correct input
def getNum():
num = -1
while num < 0:
num = int(input("\n\nEnter a non-negative integer: "))
if num < 0:
print("Invalid value. Please re-enter.")
return num
#This is to take care of number one on the list: Add number
def addOne(myList):
while True:
try:
num = (int(input("Give me a number:")))
num = int(num)
if num < 0:
raise exception
print("Thank you!")
break
except:
print("Invalid. Try again...")
myList.append(num)
#This should take care of the second on the list: Mean
def mean(myList):
myList = [ ]
listSum = sum(myList)
listLength = len(myList)
listMean = listSum / listLength
print("The mean is", listMean)
#This will take care of number three on the list: Median
def median(myList):
median = 0
sortedlist = sorted(myList)
lengthofthelist = len(sortedlist)
centerofthelist = lengthofthelist / 2
if len(sortedlist) % 2 ==0:
return sum(num[center - 1:center + 1]) / 2.0
else:
return num[center]
print("The mean is", centerofthelist)
#This will take care of the fourth thing on the list: Print the list (In order)
def sort(myList):
theList.sort(mylist)
print(myList)
#This will take care of the fifth thing on the list
def reversesort(myList):
theList.sort(reverse=True)
print(myList)
main()
After I run the program I can't get past creating the list.

Corrected code with minimum changes:
def main():
myList = []
choice = 1
while choice != 6:
if choice == 1:
option1(myList)
elif choice == 2:
option2(myList)
elif choice == 3:
option3(myList)
elif choice == 4:
option4(myList)
elif choice == 5:
option5(myList)
choice = displayMenu()
print ("\nThanks for playing!\n\n")
def displayMenu():
myChoice = 0
while myChoice not in [1, 2, 3, 4, 5]:
print("""\n\nPlease choose
1. Add a number to the list/array
2. Display the mean
3. Display the median
4. Print the list/array
5. Print the list/array in reverse order
6. Quit
""")
myChoice = int(input("Enter option---> "))
if myChoice not in [1, 2, 3, 4, 5]:
print("Invalid option. Please select again.")
return myChoice
# Option 1: Add a number to the list/array
def option1(myList):
num = -1
while num < 0:
num = int(input("\n\nEnter a non-negative integer: "))
if num < 0:
print("Invalid value. Please re-enter.")
myList.append(num)
# Option 2: Display the mean
def option2(myList):
print("The mean is ", sum(myList) / len(myList))
# Option 3: Display the median
def option3(myList):
sortedlist = sorted(myList)
if len(sortedlist) % 2:
median = myList[int(len(sortedlist) / 2)]
else:
center = int(len(sortedlist) / 2)
median = sum(myList[center-1:center+1]) / 2
print("The median is", median)
# Option 4: Print the list/array
def option4(myList):
print(sorted(myList))
# Option 5: Print the list/array in reverse order
def option5(myList):
print(sorted(myList, reverse=True))
main()
How I would do this:
The first part of the following code are a set of constants to customize the style of the menu. Then a set of functions representing each option are defined. The following 3 functions should not be modified, they generate the menu, display it and close the application. Then the main section starts, where you need to pass every option as an argument to setOptions(). The rest should not be modified either as it is the main loop.
# Menu formatting constants
MENU_HEADER = "Please choose an option:"
MENU_FORMAT = " * {:2}. {}"
MENU_QUIT_S = "Quit"
MENU_ASK_IN = "Enter option: "
MENU_INT_ER = "ERROR: Invalid integer. Please select again."
MENU_OPT_ER = "ERROR: Invalid option. Please select again."
END_MESSAGE = "Thanks for playing!"
# OPTIONS FUNCTIONS START HERE
def addElement(l):
""" Add a number to the list/array. """
n = -1
while n < 0:
try:
n = int(input("Enter a non-negative integer: "))
except ValueError:
print("It needs to be an integer.")
n = -1
else:
if n < 0:
print("It needs to be a non-negative integer.")
l.append(n)
def mean(l):
""" Calculate the mean. """
print("Mean: {:7.2}".format(sum(l) / len(l)))
def median(l):
""" Calculate the median. """
l = sorted(l)
p = int(len(l) / 2)
print("Median: {:7.2}".format(l[p] if len(l)%2 else sum(l[p-1:p+1])/2))
def oprint(l):
""" Print the list/array. """
print(sorted(l))
def rprint(l):
""" Print the list/array in reverse order. """
print(sorted(l, reverse=True))
# OPTIONS FUNCTIONS END HERE
def onQuit(l):
""" Function to execute when quitting the application. """
global quit
quit = True
print(END_MESSAGE)
def setOptions(*args):
""" Generates the menu and the options list. """
# Menu header and quit option (option 0)
menu = [MENU_HEADER]
options = [onQuit]
# Passed arguments represent texts and functions of additional options
for i, f in enumerate(args, start=1):
menu.append(MENU_FORMAT.format(i, f.__doc__.strip()))
options.append(f)
# We print the option 0 the last one
menu.append(MENU_FORMAT.format(0, MENU_QUIT_S))
# Returning both the menu and the options lists
return tuple(menu), tuple(options)
def displayMenu(menu):
""" Display the menu and get an option that is an int. """
while True:
for line in menu:
print(line)
try:
choice = int(input(MENU_ASK_IN))
except ValueError:
print(MENU_INT_ER)
else:
return choice
if __name__ == '__main__':
# Pass the option functions to the setOptions function as arguments
menu, options = setOptions(
addElement,
mean,
median,
oprint,
rprint
)
# Initiate the needed variables and start the loop
l = []
quit = False
while not quit:
c = displayMenu(menu)
try:
f = options[c]
except IndexError:
print(MENU_OPT_ER)
else:
f(l)

There is an indentation error inside your function addOne.
myList.append(num) is inside the while loop, and just before that you have a break, so the number is never appended to the list because we have left the loop already.

How to repeat blocks of code in Python

I've created a code that allows a user to view the average score of the values that are in the file. In Example the Text File would look like the following:
Text File For Class 1: it is similar for each text file ; 2 and 3. just different names and values
Matt 2
Sid 4
Jhon 3
Harry 6
There are 3 classes altogether in which the user is prompted to choose which class they want to preview.
Code:
def main_menu():
print ("\n Main Menu ")
print ("1.Average Score of class = 'avg'")
main_menu()
option = input("option [avg]: ")
option_class = input("class: ")
one = "1.txt"
two = "2.txt"
three = "3.txt"
if option.lower() == 'avg' and option_class == '1':
with open(one) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
print ("Average of Class is: ", avg)
if option.lower() == 'avg' and option_class == '2':
with open(two) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
print ("Average of Class is: ", avg)
if option.lower() == 'avg' and option_class == '3':
with open(three) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
print ("Average of Class is: ", avg)
Question
If i wanted to Keep Repeating the code above so that the user can keep using it until they want to exit. so, is it possible to put the code into a while loop and only stop the code if the user wants to, i.e the user is prompted if they want to choose another option and class.
NB: there will be other options such as alphabetical order however right now i only want to know how to do it for the average section.

Best thing you can do is to make a loop for user input and write a function for listing the file.
def main_menu():
print ("\n Main Menu ")
print ("1.Average Score of class = 'avg'")
main_menu()
option = ""
options = ["1", "2", "3"]
one = "1.txt"
two = "2.txt"
three = "3.txt"
def read_text_file(file): # standalone function for viewing files to reduce duplicate code
file += ".txt"
with open(file) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
print ("Average of Class is: ", avg)
while True:
option = input("option [avg]: ").lower()
if option == "exit":
break # checks if user want to exit a program
else:
option_class = input("class: ")
if option == 'avg' and option_class in options:
read_text_file(option_class)
else:
print("nothing to show, asking again")
print("end of program")

As I mentioned in the comment section, you should leverage the power of functions here. By breaking down your components to manageable pieces, you actually afford yourself readability and flexibility. See code below, where I have two functions, one for averages and one for totals.
def get_class_average(class_number):
filename = "{0}.txt".format(class_number)
try:
with open(filename) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
return avg
except:
print "No file with that name found."
def get_class_total(class_number):
filename = "{0}.txt".format(class_number)
try:
with open(filename) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
return b
except:
print "No file with that name found."
def check_class_number(string_input):
try:
int(string_input)
return True
except ValueError:
return False
if __name__ == "__main__":
while True:
input_val = raw_input(
"Enter class number (enter 'exit' to quit program): ")
if input_val == 'exit':
break
if check_class_number(input_val): # If it's a valid class number.
method = raw_input("Enter method: ")
if method == 'avg':
avg = get_class_average(int(input_val))
print "The average of Class {0} is {1}".format(input_val, avg)
elif method == 'sum':
total = get_class_total(int(input_val))
print "The total of Class {0} is {1}".format(input_val, total)
else:
print "That is not a valid class number."
continue
Sample run:
The really fun part here is that you can even refactor get_class_average and get_class_total to be a single function that checks if the passed in method is avg or sum and returns the respective values from there (this is easily doable since you have practically the same lines of code for both functions, get_class_average just has an extra division involved).
Have fun.

Yes, you can just put your code within a while-loop and prompt the user for input:
def main_menu():
print ("\n Main Menu ")
print ("1.Average Score of class = 'avg'")
# End main_menu()
one = "1.txt"
two = "2.txt"
three = "3.txt"
keepGoing = True
while(keepGoing):
main_menu()
option = input("option [avg]: ")
option_class = input("class: ")
if option.lower() == 'avg' and option_class == '1':
with open(one) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
print ("Average of Class is: ", avg)
if option.lower() == 'avg' and option_class == '2':
with open(two) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
print ("Average of Class is: ", avg)
if option.lower() == 'avg' and option_class == '3':
with open(three) as f:
the_list = [int(l.strip().split()[-1]) for l in f]
b = sum(the_list)
length = len(the_list)
avg = float(b) / length if length else 0
print ("Average of Class is: ", avg)
# Prompt user for input on whether they want to continue or not:
while(True):
keepGoingStr = input("Would you like to continue? (Y/N)\n>>> ").lower()
if(keepGoingStr[0] == 'y'):
# Keep going
keepGoing = True
break
elif(keepGoingStr[0] == 'n')
# Stop
keepGoing = False
break
else:
print("Sorry, your input did not make sense.\nPlease enter either Y or N for yes or no.")
# end if
# end while - keep going input
# End While(keepGoing)
As mentioned in the comments, though, you should consider breaking up your code into functions.

Do while loops have local variables in Python?

I am trying to use a while statement like so:
o = 0
while o == 0:
try:
n = int(raw_input("Which number do you want to begin with?"))
o = 1
except:
o = 0
print "Please use a valid number."
However, when I try to use variable n later, it gives me the "local variable 'n' referenced before assignment' UnboundLocalError. That means that n cannot be recognized as a variable in the def I am using, because it only exists in the while statement? Is this possible?
The whole code:
import time
from sys import argv
import os
os.system("cls")
print "Welcome to Number counter 2.0!"
a = True
def program():
global a
if a == False:
os.system("cls")
o = 0
while o == 0:
try:
n = int(raw_input("Which number do you want to begin with?"))
o = 1
except:
o = 0
print "Please use a valid number."
if n == "/historyKeep false":
if a == False:
print "Command historyKeep is already set to false."
else:
a = False
print "Command set successfully."
elif n == "/historyKeep true":
if a == True:
print "Command historyKeep is already set to true."
else:
a = True
print "Command set successfully."
if n == "/historyKeep false":
n = raw_input("Which number do you want to begin with?")
elif n == "/historyKeep true":
n = raw_input("Which number do you want to begin with?")
d = raw_input("How many seconds between each number?")
d = int(d)
total_s = n * d
while n > 0:
print n
time.sleep(d)
n = n - 1
print "Done in", total_s, "seconds in total!"
end_q = raw_input("Exit or retry? (e/r)")
if end_q == "e":
os.system("cls")
print "Exiting."
time.sleep(0.5)
os.system("cls")
print "Exiting.."
time.sleep(0.5)
os.system("cls")
print "Exiting..."
time.sleep(0.5)
os.system("cls")
exit(0)
elif end_q == "r":
program()
program()

You set a = True at the beginning. You then test if a == False and only set n if it is. But then you test n == "/history.... n has not been set at this point.
You need to make sure n is assigned before you use it. It is not enough to just mention it in a branch that is not taken.

n is not defined in the scope that you are trying to use it to fix this define it outside of the while loop and the if statement the while loop is in:
global a
n = 0
Then when you ask the user for what number to start with, that value will replace 0, and you should be good to go. Also instead of declaring global a, why not just make a an input argument for the program() function?

Just to make sure, declare n outside of the loop first:
n = None
while True:
try:
n = int(raw_input("Text..."))
break
except:
print("Please enter a valid number!")
Note: Usually, you would use break to exit a loop. This is because your method requires an extra variable, which uses more memory (not much, but if you keep doing it, it will stack up).