Defining the type of variable! PYTHON

Question

I am doing a small console program. You input the data and then program puts it in .txt file. The data is: Country Year of birth Month of birth Day of birth Real name Nickname

I decided to do a definition for every variable, so if user types an integer in "Country" it gives him a warning and vice versa. Here is the code:

countryU = input('Страна проживания ')
yearU = input('Год рождения ')
monthU = input('Месяц рождения (его порядковый номер) ')
dayU = input('День рождения ')
nameU = input('Имя ')
nicknameU = input('Никнейм ')
aaaaa = 5
from random import *
u = randint(1,1000000000000)
uinfoname = str(u) + '.txt'

if type(countryU) == str:
    if type(yearU) == int:
        if type(monthU) == int:
            if type(dayU) == int:
                if type(nameU) == str:
                    if type(nicknameU) == str:
                        if countryU == '':
                            print('Вы ввели не все данные! Перезапустите программу и введите все.')
                            input('Press any key to exit...')
                        else:
                            if yearU == '':
                                print('Вы ввели не все данные! Перезапустите программу и введите все.')
                                input('Press any key to exit...')
                            else:
                                if monthU == '':
                                    print('Вы ввели не все данные! Перезапустите программу и введите все.')
                                    input('Press any key to exit...')
                                else:
                                    if dayU == '':
                                        print('Вы ввели не все данные! Перезапустите программу и введите все.')
                                        input('Press any key to exit...')
                                    else:
                                        if nameU == '':
                                            print('Вы ввели не все данные! Перезапустите программу и введите все.')
                                            input('Press any key to exit...')
                                        else:
                                            if nicknameU == '':
                                                print('Вы ввели не все данные! Перезапустите программу и введите все.')
                                                input('Press any key to exit...')
                                            else:
                                                if (len(str(nicknameU)) < aaaaa):
                                                    print('Твой никнейм недостаточно длинный! (минимум 5 символов) Перезагрузите программу и введите все правильно.')
                                                    input('Press any key to exit...')
                                                else:
                                                    print('Вы -', nameU, 'из страны', countryU, '')
                                                    print('Ваша дата рождения: месяц', monthU, 'число', dayU, 'год', yearU, '')
                                                    print('Ваш никнейм на сайте -', nicknameU, '.')
                                                    print('Приятного времяпрепровождения!')
                                                    output = open(uinfoname, 'x')
                                                    print(countryU, file=output)
                                                    print(yearU, file=output)
                                                    print(monthU, file=output)
                                                    print(dayU, file=output)
                                                    print(nameU, file=output)
                                                    print(nicknameU, file=output)
                                                    output.close()
                                                    input('Press any key to exit...')
                    else:
                        print('Никнейм не должен содержать специальные символы или цифры!')
                        input('Press any key to exit...')
                else:
                    print('Имя не должно содержать специальные символы или цифры!')
                    input('Press any key to exit...')
            else:
                print('День вашего рождения является числом!')
                input('Press any key to exit...')
        else:
            print('Месяц вашего рождения является числом!')
            input('Press any key to exit...')
    else:
        print('Год вашего рождения является числом!') #pay attention to this string, this is the problem
        input('Press any key to exit...')
else:
    print('Название вашей страны не может содержать специальные символы или цифры! (Если название вашей страны все-таки их содержит, напишите название без них.')
    input('Press any key to exit...')

Don't mind, I am Russian and I use Russian language. Well, to the problem: When I run the program and type everything correctly (integer to integer, string to string), it says: Год вашего рождения является числом! (the problem string) It means "Your year of birth should be a number!" And even if I type the country incorrectly (integer), it says the same. So whatever I type, it gives me that string. I also used isinstance, but it is much worse here. Please help me!

By the way, everything else works correctly. And when I remove the test for an integer/string, it also works correctly. — user12828597
– user12828597, Commented Feb 2, 2020 at 15:56
type(countryU) will always be str, because input always returns a str. — chepner
– chepner, Commented Feb 2, 2020 at 15:57
If only there were standard library functions that tell you if a string consist entirely of digits or letters. (Hint: there are.) — Jongware
– Jongware, Commented Feb 2, 2020 at 15:59
Btw, panoramic monitor required to read this code... just joking, too many nested if/else statements. — oz19
– oz19, Commented Feb 2, 2020 at 16:05
Try using elif statements instead of nested else if, to make the code more readable. — TVASO
– TVASO, Commented Feb 2, 2020 at 16:15

TVASO · Accepted Answer · 2020-02-02 15:58:16Z

1

The input() method always returns a string. If you want the corresponding variable to be an integer, you should cast the string into an integer using the int() method.

So:

year = int(input("Please enter a year"))

The same goes for other types of variables, but with the float() method for floats and so on.

answered Feb 2, 2020 at 15:58

TVASO

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Comments

Ivan · Accepted Answer · 2020-02-02 16:00:01Z

0

All your inputs are strings, you can handle integers as int(str_var)

answered Feb 2, 2020 at 16:00

Ivan

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Comments

chepner · Accepted Answer · 2020-02-02 16:05:13Z

Much of your code is catering to a case that can never happen, namely that the return value of input is not a str value. Further, if you simply exit immediately whenever you use input('Press any key to exit...'), there is no need to indent the following code. With that in mind, you code instantly reduces to something like

from random import *

countryU = input('Страна проживания ')
yearU = input('Год рождения ')
monthU = input('Месяц рождения (его порядковый номер) ')
dayU = input('День рождения ')
nameU = input('Имя ')
nicknameU = input('Никнейм ')
aaaaa = 5
u = randint(1,1000000000000)

uinfoname = str(u) + '.txt'


if countryU == '':
    print('...')
    input('Press any key to exit...')
    sys.exit()

if yearU == '':
    print('...')
    input('Press any key to exit...')
    sys.exit()

if monthU == '':
    print('...')
    input('Press any key to exit...')
    sys.exit()

if dayU == '':
    print('...')
    input('Press any key to exit...')
    sys.exit()

if nameU == '':
    print('...')
    input('Press any key to exit...')
    sys.exit()

if nicknameU == '':
    print('...')
    input('Press any key to exit...')
    sys.exit()

if (len(str(nicknameU)) < aaaaa):
    print('...')
    input('Press any key to exit...')
    sys.exit()

print('Вы -', nameU, 'из страны', countryU, '')
print('Ваша дата рождения: месяц', monthU, 'число', dayU, 'год', yearU, '')
print('Ваш никнейм на сайте -', nicknameU, '.')
print('Приятного времяпрепровождения!')
output = open(uinfoname, 'x')
print(countryU, file=output)
print(yearU, file=output)
print(monthU, file=output)
print(dayU, file=output)
print(nameU, file=output)
print(nicknameU, file=output)
output.close()
input('Press any key to exit...')

Allaye · Accepted Answer · 2020-02-02 16:08:58Z

0

userinput = input ("Enter your Age")
try:
   value = int(userinput)
   print("Input is an integer number. Number = ", valuee)
except ValueError:
  try:
    value = float(userinput)
    print("Input is a float  number. Number = ", value)
  except ValueError:
      print("No.. input is not a number. It's a string")

edited Feb 2, 2020 at 16:08

answered Feb 2, 2020 at 16:03

Allaye

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Comments

t0mas · Accepted Answer · 2020-02-02 16:11:18Z

To remove the amount of IF statements you have, you can simply ask that the input is an integer or string when you are asking for the variable in the first few lines, for example:

countryU = str(input('Страна проживания '))
yearU = int(input('Год рождения '))

This way you don't need to check if the input was an integer or string as it will just act like an integer or string. If an charaters is inputted for the year python will send back an error. to fix this you can put:

if countryU != int():
print('Год вашего рождения является числом!') # remember to indent/tab this line!!

the '!=' means is NOT equal to, so if the country is not an integer output " Год вашего рождения является числом!".

I hope this helps, this means you don;t need to check if it is a str/int because python does it for you, you only need to check if it IS NOT a srt/int.

ChufanSuki · Accepted Answer · 2020-02-02 16:18:10Z

input([prompt]) always return a string type.

If the prompt argument is present, it is written to standard output without a trailing newline. The function then reads a line from input, converts it to a string (stripping a trailing newline), and returns that.

If you want to do type checking, you can use isinstance(object, classinfo) which return True if the object argument is an instance of the classinfo argument and raise a exception when meeting invalid value.

A example:

def checkType(s):
    if not isinstance(s, str):
        # This is (a simple form of) how you raise your own custom exception:
        raise Exception('It must be a string')
    else: 
        pass

print(checkType('abc'))
print(checkType(1))
print("This line will never run!")

LeopardL GD · Accepted Answer · 2020-02-08 16:26:37Z

0

You should keep in mind that input() always gives you a string. Try this:

try:
    mathproblem = int(input('23516 * 84818^81'))
except ValueError:
    print('Dude you should type a number...')

answered Feb 8, 2020 at 16:26

LeopardL GD

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