Attributeerror: 'Int' Object Has No Attribute 'Isdigit'
NumOfYears = 0 Cpi = Eval(Input("Enter the Cpi for July 2015: ")) If Cpi. Isdigit(): While Cpi < (Cpi * 2): Cpi *= 1.025 numOfYears += 1 Print("Consumer Prices...
numOfYears = 0
cpi = eval(input("Enter the CPI for July 2015: "))
if cpi.isdigit():
while cpi < (cpi * 2):
cpi *= 1.025
numOfYears += 1
print("Consumer prices will double in " + str(numOfYears) + " years.")
while not cpi.isdigit():
print("Bad input")
cpi = input("Enter the CPI for July 2015: ")
I'm getting the following error.
AttributeError: 'int' object has no attribute 'isdigit'
Since I'm new to programming, I don't really know what it's trying to tell me. I'm using the if cpi.isdigit(): to check to see if what the user entered is a valid number.
4 Answers
As documented here isdigit() is a string method. You can't call this method for integers.
This line,
cpi = eval(input("Enter the CPI for July 2015: "))
evaluates the user input to integer.
>>> x = eval(input("something: "))
something: 34
>>> type(x)
<class 'int'>
>>> x.isdigit()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'int' object has no attribute 'isdigit'
But if you remove eval method (you should better do that),
>>> x = input("something: ")
something: 54
>>> type(x)
<class 'str'>
>>> x.isdigit()
True
everything will be fine.
by the way using eval without sanitizin user input may cause problems
consider this.
>>> x = eval(input("something: "))
something: __import__('os').listdir()
>>> x
['az.php', 'so', 'form.php', '.htaccess', 'action.php' ...
Use this:
if(str(yourvariable).isdigit()) :
print "number"
isdigit() works only for strings.
numOfYears = 0
# since it's just suppposed to be a number, don't use eval!
# It's a security risk
# Simply cast it to a string
cpi = str(input("Enter the CPI for July 2015: "))
# keep going until you know it's a digit
while not cpi.isdigit():
print("Bad input")
cpi = input("Enter the CPI for July 2015: ")
# now that you know it's a digit, make it a float
cpi = float(cpi)
while cpi < (cpi * 2):
cpi *= 1.025
numOfYears += 1
# it's also easier to format the string
print("Consumer prices will double in {} years.".format(numOfYears))
eval() is very dangerous! And int() built-in function can convert string to digit.
If you want to catch the error if user didn't enter a number, just use try...except like this:
numOfYears = 0
while numOfYears == 0:
try:
cpi = int(input("Enter the CPI for July 2015: "))
except ValueError:
print("Bad input")
else:
while cpi < (cpi * 2):
cpi *= 1.025
numOfYears += 1
print("Consumer prices will double in", numOfYears, "years.")
Robert Thorne covers electric vehicle innovations, autonomous driving systems, global mobility trends, and automotive engineering developments.
