Leading Digit Extractor
Extract the leading decimal digit of an integer, ignoring its sign.
Description
Extract the leading decimal digit of an integer, ignoring its sign.
Extract the leading decimal digit of an integer, ignoring its sign.
When to use Leading Digit Extractor
Use this tool to test or transform exact integers according to the named number-theory definition, for education, validation, or algorithm checks.
- Integer
- An integer input.
How the calculation works
The formula below determines the tool output. Leading digit: The calculated leading digit.1
leading digit = floor(|n| / 10^floor(log₁₀|n|)) Limitations and assumptions
This tool applies an exact integer definition within JavaScript's safe-integer range. It is not an arbitrary-precision factorization or proof system, so do not use rounded measurements or integers beyond the accepted domain as though they were exact.
Alternative or Complementary approaches
Complement a number-property result with its factorization, divisors, digit representation, or a second independent predicate. A true result establishes only the named property and does not imply other properties such as primality.
References
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Leading digit — Wikipedia contributors
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