csignum-fast 1.0.0

High-performance universal sign function

csignum-fast

A robust, high-performance C++ implementation of the universal sign function for Python. Released on December 25, 2025 — The Christmas Edition.

Key Features

1. Uniform Results: Always returns only -1, 0, or 1 as an int for valid numeric comparisons.
2. Correct Edge Case Handling:
   • sign(+0.0) and sign(-0.0) return 0.
   • sign(inf) returns 1, sign(-inf) returns -1.
   • For any NaN (float NaN, Decimal NaN, etc.), it returns math.nan (float).
3. Comprehensive Duck Typing: Delegates comparisons to the argument's class. Works seamlessly with:
   • Built-in int (including arbitrary-precision), bool, and float.
   • fractions.Fraction and decimal.Decimal.
   • Any existing and future objects that support rich comparisons with numbers.
4. Informative Error Handling for Easy Debugging: Provides clear, descriptive TypeError messages when passed non-numeric, non-scalar, or incomparable arguments.
5. High Performance: Implemented in C++ using a branchless ternary logic approach (no if-else chains), ensuring maximum execution speed.
6. Thoroughly Tested: Tested on 51 cases including different types, edge cases, new custom class, and inappropriate arguments.

Installation

pip install csignum-fast

Usage

from signum import sign
from decimal import Decimal

print(sign(-10**100))       # -1
print(sign(3.14))           #  1
print(sign(Decimal("0.0"))) #  0
print(sign(float('-nan')))  # nan