isdecimal() : Check if all chars are decimal numbers or not in a string in Python

isdecimal()

Returns True if all chars are decimal ( 0 to 9) in a string, Otherwise False is returned.

my_str='12345'print(my_str.isdecimal())      # Output is True
my_str='234ab'print(my_str.isdecimal())      # Output is False
my_str='234.45'print(my_str.isdecimal())      # Output is False

Difference between isnumeric(), isdigit() and isdecimal()

Use google to search translate 1234 to chinese , then use the output like this.

my_str='一千二百三十四'print(my_str.isnumeric())  # Trueprint(my_str.isdigit())    # False print(my_str.isdecimal())  # False

One more example

my_str = '2²'print(my_str.isnumeric())  # Trueprint(my_str.isdigit())    # True print(my_str.isdecimal())  # False

my_str = '½'print(my_str.isnumeric())  # Trueprint(my_str.isdigit())    # False print(my_str.isdecimal())  # False

isdigit() will allow only digits 0-9

Example 1: Basic Usage of isdecimal()

text = "12345"
print(text.isdecimal())  # Output: True

Example 2: Using isdecimal() with Non-decimal Characters

text = "123.45"
print(text.isdecimal())  # Output: False

Example 3: Difference Between isdecimal() and isnumeric()

The `isnumeric()` function returns True for non-standard decimal characters, while `isdecimal()` does not.

text = "123\u00B2"  # ² is superscript 2
print(text.isdecimal())  # Output: False
print(text.isnumeric())  # Output: True

Applications of isdecimal()

Input Validation: Confirm that input consists only of basic decimal numbers.
Data Filtering: Separate purely numeric strings from mixed content.

All String methods

isalnum() isalnum() Python- Tutorials

Subhendu Mohapatra

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isdecimal(): Check for Decimal Characters