metrima 0.2.1

Just another (cool) no-deps math library

Metrima

A small, comprehensive math library with fixed-point arithmetic precision.

Overview

Metrima is a Python math library that implements the Fx (Fixed-point) class to provide precise decimal arithmetic without the floating-point precision issues common in standard Python operations.

Features

• Fixed-Point Arithmetic: Avoid floating-point precision errors
• Full Operator Support: All standard math operations (+, -, *, /, //, %, **)
• Type Conversions: Seamless conversion between Fx, int, float, and str
• Comparison Operations: Complete set of comparison operators
• In-place Operations: Support for +=, -=, *=, etc.
• Unary Operations: Negation, absolute value, and rounding

Installation

pip install metrima

Quick Start

from metrima import Fx, fx

# Create fixed-point numbers
a = Fx("1.432")
b = fx(5.1234)  # Convenience function

# Perform arithmetic
result = a + b
print(result)  # 6.5554

# Mix with regular numbers
c = Fx(10.0) - 2.45
print(c)  # 7.55

# Complex expressions
d = (Fx(2.5) + Fx(3.5)) * Fx(4) - Fx(10) / Fx(2)
print(d)  # 19.0

Why Metrima?

Standard Python floating-point arithmetic can produce unexpected results:

# Python's float arithmetic
0.1 + 0.2  # 0.30000000000000004 😱

# Metrima's Fx arithmetic
Fx(0.1) + Fx(0.2)  # 0.3 ✨

The Fx Class

The Fx class stores numbers as scaled integers, maintaining precision by tracking the decimal scale separately.

Creating Fx Objects

# From string (recommended for decimals)
x = Fx("3.14159")

# From int
y = Fx(42)

# From float
z = Fx(2.5)

# Using the fx() convenience function
w = fx("1.23")

Arithmetic Operations

a = Fx("10.5")
b = Fx("2.5")

a + b   # Addition: 13.0
a - b   # Subtraction: 8.0
a * b   # Multiplication: 26.25
a / b   # Division: 4.2
a // b  # Floor division: 4.0
a % b   # Modulo: 0.5
a ** 2  # Power: 110.25

Comparisons

Fx("2.0") == Fx("2")    # True
Fx(3) != 3              # False
Fx("1.5") > Fx("1.4")   # True
Fx("1.2") < 2           # True

Type Conversions

x = Fx("3.14")

float(x)  # 3.14
int(x)    # 3
str(x)    # "3.14"
bool(x)   # True

Testing

Metrima includes comprehensive test suites comparing its accuracy against both standard Python arithmetic and Python's Decimal class.

Run Interactive Tests

metrimatest

This launches an interactive menu where you can choose:

1. Competition Demo - Compare Metrima vs Python vs Decimal
2. Fx Class Testing - Detailed unit tests for the Fx class

Test from Code

from metrima import test_main

test_main()  # Run the full test suite

API Reference

Basic Functions

from metrima import add, subtract, mul, div

add(a, b)       # Addition
subtract(a, b)  # Subtraction
mul(a, b)       # Multiplication
div(a, b)       # Division

Fx Methods

• __add__, __sub__, __mul__, __truediv__, __floordiv__, __mod__, __pow__
• __neg__, __pos__, __abs__, __round__
• __eq__, __ne__, __lt__, __le__, __gt__, __ge__
• __int__, __float__, __str__, __repr__, __bool__

Requirements

• Python >= 3.14
• tinycolors (for colorized test output)

Version

Current version: 0.2.0

License

MIT

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.