Given a string, write a Python program to find whether a string contains only numbers or not. Let’s see a few methods to solve the above task.
Method #1: Using isdigit() method
# Python3 code to demonstrate # how to check whether string contains # only numbers or not # Initialising string ini_string1 = '1234556' ini_string2 = 'ab123bc' # printing initial string print ("Initial Strings : ", ini_string1, ini_string2) # Using isdigit() if ini_string1.isdigit(): print ("String1 contains all numbers") else: print ("String1 doesn't contains all numbers") if ini_string2.isdigit(): print ("String2 contains all numbers") else: print ("String2 doesn't contains all numbers")
Output:
Initial Strings : 1234556 ab123bc String1 contains all numbers String2 doesn't contains all numbers
Method #2: Using regex
# Python3 code to demonstrate # how to check whether string contains # only numbers or not import re # Initialising string ini_string1 = '1234556' ini_string2 = 'ab123bc' # printing initial string print ("Initial Strings : ", ini_string1, ini_string2) # Using regex() if re.match('^[0-9]*$', ini_string1): print ("String1 contains all numbers") else: print ("String1 doesn't contains all numbers") if re.match('^[0-9]*$', ini_string2): print ("String2 contains all numbers") else: print ("String2 doesn't contains all numbers")
Output:
Initial Strings : 1234556 ab123bc String1 contains all numbers String2 doesn't contains all numbers
Method #3: Using try/exception
# Python3 code to demonstrate # how to check whether string contains # only numbers or not # Initialising string ini_string1 = '1234556' ini_string2 = 'abc123' # printing initial string print ("Initial Strings : ", ini_string1, ini_string2) # Using try / exception: try: num = int(ini_string1) print ("String1 contains only digits") except: print ("String1 doesn'tcontains only digits") try: num = int(ini_string2) print ("String2 contains only digits") except: print ("String2 doesn't contains only digits")
Output:
Initial Strings : 1234556 abc123 String1 contains only digits String2 doesn't contains only digits