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+--- Thread: Need help with isdigit() and isalpha() function (/thread-19971.html)
Need help with isdigit() and isalpha() function - Gateux - Jul-22-2019
I need to write a program that has these conditions:
- Length must be exactly 9
- The first letter must be S, T, F or G
- Must consist of 7 digits
- Reference letter must be A to Z or a to z
Expected Output:
Output:Enter String: S1234567A
Valid String
Enter String: X123456789B
Error, Length must be exactly 9
Enter String: S12345XXB
Error, Must consist of 7 digitsMy Code:
def main():
enterstr = input("Enter String: ")
firstletter = ["S", "T", "F", "G"]
refletter = ['A', 'B', 'C', 'D']
if enterstr.isdigit() < 7:
print("Error, Must consist of 7 digits")
elif enterstr.isalpha() [0] != firstletter:
print("Error, The first letter must be S, T, F or G")
elif enterstr.isalpha() [-1] != refletter:
print("Error, Reference letter must be A to Z or a to z")
elif enterstr.count < 9:
print("Error, Length must be exactly 9")
else:
print("Valid String")
main()I keep getting the output "Error, Must consist of 7 digits" no matter how many characters the String is. Need your advise, thanks.
RE: Need help with isdigit() and isalpha() function - metulburr - Jul-22-2019
Isdigit and isalpha return true or false
len() returns the length of the object
RE: Need help with isdigit() and isalpha() function - jefsummers - Jul-22-2019
You are trying to do too many things at once. Although you will get the skills to combine some of these processes, I strongly suggest you tackle the requirements one at a time, like this...
def main():
enterstr = input("Enter String: ")
valid_string = True
""" First test - is the length exactly 9 """
if len(enterstr) != 9 :
""" Print the error message and change the flag"""
""" Will leave the first letter check to you
Next must contain 7 digits """
digit_count = 0
for index in range(0,8):
if enterstr[index].isdigit():
digit_count += 1
"""Now check to see if the digit count passes, print error if not, adjust the flag.
"""You can write the rest from here """
main()