function_name is not defined error - python-3.x

Question

I want to write a function in python that tells if the number I give is prime, my code so far is:
def enter_input():
n=input("Enter the number to be checked\n")
return n
def check():
o=int(enter_input())
r=o
print(type(o))
print(type(r))
bool=True
for i in range(2,r,1):
if(o%i==0):
return False
return True
def display():
print("Entered Number Is {0}".format(p))
print("The Number is a Prime:{0}".format(check()))
enter_input()
check()
display()
But I get this error after input the numer:
RunTime:-
Enter the number to be checked
23
Traceback (most recent call last):
File "Chech_Prime.py", line 8, in check
o=int(enter_input())
NameError: name 'enter_input' is not defined
Repl Closed
Where did I go wrong? This was my first try with function calling, It seems like the place i called the enter_input() function could not find it. Thanks for any help

Answer 1

You write somethings a little odd, so I will explain why this should do what you are specting:
This is your code, I will comment between lines:
def enter_input():
n=input("Enter the number to be checked\n")
return n
def check(): # you create the check function, and then a display function, and is not necesary, because you want to do both thinks in the same function
o=int(enter_input()) # you call this function a lot of times, and you only want to input the value once, so, is better to call the input method inside the function
r=o # is better to name variables more descriptive, I mean, check() as a function, what checks? maybe you want to call it is_prime(), more descriptive, o and p... doesn't say anything, but input sounds better
print(type(o))
print(type(r)) #this auxiliar variable is not needed
bool=True
for i in range(2,r,1):
if(o%i==0):
return False
return True
def display():
print("Entered Number Is {0}".format(p))
print("The Number is a Prime:{0}".format(check()))# here you again call the function, and again it ask to you to add a input... not good
enter_input()
check() # and again.. three times, that's so confusing even to follow when you are adding the inputs
display()
My way to do it will be:
def print_is_prime():
value_to_eval=int(input("Enter the number to be checked\n"))
print("the type of the value is " + str(value_to_eval.__class__.__name__))
is_prime =True #initial value is correct
for i in range(2,value_to_eval,1):
if(value_to_eval%i==0):
is_prime = False #here, you detect is not prime
break # so with break you can avoid to execute innecesary all the loop
is_prime = True and is_prime # with and operator, true is the neutral, so the value will be always the other value, in this case, is_prime, this like 0 + x, the value will be always x
print("Entered Number Is {0}".format(value_to_eval))
print("The Number is a Prime:{0}".format(is_prime))
print_is_prime()