TypeError: '<' not supported between instances of 'NoneType' and 'int'
I have looked for an answer in Stack Overflow and found that I should be taking an int(input(prompt)), but that's what I am doing
def main(): while True: vPopSize = validinput("Population Size: ") if vPopSize < 4: print("Value too small, should be > 3") continue else: break
def validinput(prompt): while True: try: vPopSize = int(input(prompt)) except ValueError: print("Invalid Entry - try again") continue else: break5 Answers
This problem also comes up when migrating to Python 3.
In Python 2 comparing an integer to None will "work," such that None is considered less than any integer, even negative ones:
>>> None > 1
False
>>> None < 1
TrueIn Python 3 such comparisons raise a TypeError:
>>> None > 1
Traceback (most recent call last): File "<stdin>", line 1, in <module>
TypeError: '>' not supported between instances of 'NoneType' and 'int'
>>> None < 1
Traceback (most recent call last): File "<stdin>", line 1, in <module>
TypeError: '<' not supported between instances of 'NoneType' and 'int'you need to add a return in your function to get the number you input, otherwise it return an implicit None
def validinput(prompt): while True: try: return int(input(prompt)) # there is no need to use another variable here, just return the conversion, # if it fail it will try again because it is inside this infinite loop except ValueError: print("Invalid Entry - try again")
def main(): while True: vPopSize = validinput("Population Size: ") if vPopSize < 4: print("Value too small, should be > 3") continue else: breakor as noted in the comments, make validinput also check if it is an appropriate value
def validinput(prompt): while True: try: value = int(input(prompt)) if value > 3: return value else: print("Value too small, should be > 3") except ValueError: print("Invalid Entry - try again")
def main(): vPopSize = validinput("Population Size: ") # do stuff with vPopSizeChanging None value worked for me np.nan documentation
df_gpa.replace(to_replace=[None], value=np.nan, inplace=True)code before
def validate(self): df = self.df['column_name'] print(df) for i in df: if i < 0: raise Exception(f"range is lower than 0.0: {i}") if i > 150: raise Exception(f"range is higher than 150: {i}")code after
def validate(self): df = self.df['column_name'] df.replace(to_replace=[None], value=np.nan, inplace=True) print(df) for i in df: if i < 0: raise Exception(f"range is lower than 0.0: {i}") if i > 150: raise Exception(f"range is higher than 150: {i}")Try: def validinput(prompt): print(prompt) # this one is new!! while True: try: vPopSize = int(input(prompt)) except ValueError: print("Invalid Entry - try again") continue else: breakAnd you will notice when the function is called.
The problem is that validinput() does not return anything. You'd have to return vPopSize
0should remove print() from the return of the function, so take the value and print it from outside
