Check if a string contains a number

Python ninja techniques: Efficient and clear methods

There are several ways to check whether a string contains a number. Each has its own charm. Let's unmask them.

Unleashing any() and str.isdigit()

This little combo packs a punch; it's a quick answer to your conundrum.

# Python chakra unleashed
def contains_digit(s):
    return any(char.isdigit() for char in s)
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Regular expressions: Coding with a wand!

Want to be a Hogwarts graduate? Master regular expressions (RegEx). Did I say Hogwarts? I meant Regexwarts. Let's swing that wand!

import re

# Swish and flick!
def contains_number(s):
    return bool(re.search(r'\d', s))
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Given a regular need for the same regex pattern, pre-compile it. Performance matters, folks!

# Minimalist magic with compiled RegEx.
number_pattern = re.compile(r'\d')
def contains_number(s):
    return bool(number_pattern.search(s))
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Decision time!

Choose any() with str.isdigit() for when simplicity is king. Fetch the big guns (RegEx) when faced with complex patterns.

Beyond simple digits: The Matrix Unveiled

Numbers can be sneaky. They might hide behind decimals or commas. Watch out for allies of numbers too.

Decimals and commas: Numbers in disguise!

Detecting decimals and commas hiding in a string:

# They see me rollin', They hatin'
def contains_decimal_number(s):
    return bool(re.search(r'\d[\d.,]*', s))
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Excluding 100% alphabetic or numeric strings

Purely numeric or alphabets entries don't fit our 'numbers hiding agenda'. Let's rule them out with str.isalpha().

# Pure no more.
def contains_mixed_content(s):
    return not s.isalpha() and any(char.isdigit() for char in s)
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Extracting numbers: It's like Easter egg hunt!

Find and extract all numbers, even those pretending to be commas or dots.

# Turns out, there's a party in every string!
def extract_numbers(s):
    return re.findall(r'[\d.,]+', s)
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Generator Expressions: The unsung hero

Consider using generator expressions. They are light on memory, and that's no joke!

# Brains over brawn, folks!
def contains_digit_gen(s):
    return any(char.isdigit() for char in s)
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