Numeral System Converter and Expression Evaluator

A Python module for converting numbers between numeral systems (2-36) and evaluating cross-base mathematical expressions.
Key Features:

• Integer/fractional conversions
• Mixed-base calculations (+, -, *, /, ^, parentheses)
• Minimum base detection
• Custom error handling

Quick Start

1. Convert Numbers

from BaseKit import rebase

# Integer conversions
print(rebase("1011_2", to_base=10))  # "11_10" (binary -> decimal)
print(rebase("FF_16", to_base=2))  # "11111111_2" (hex -> binary)

# Fractional conversions
print(rebase("3.14_10", to_base=16))  # "3.23D7_16" (rounded to 4 digits)
print(rebase("A.8_16", to_base=10))  # "10.5_10" (hex -> decimal)

# Custom precision
print(rebase("0.1_2", to_base=10, rounding=6))  # "0.5_10"

2. Evaluate Cross-Base Expressions

from BaseKit import eval2dec, rebase

# Mixed-base arithmetic
print(eval2dec("10_2 + A_16"))  # "12_10" (2 + 10 = 12)
print(eval2dec("FF_16 - 10_10"))  # "245_10" (255 - 10 = 245)

# Advanced operations
print(eval2dec("(10_8 + 20_16) / 2_10"))  # "20.0_10" (8 + 32 = 40; 40 / 2 = 20)
print(eval2dec("2_10 ^ 4_10"))  # "16_10" (2вЃґ = 16)

print(rebase("f_30*10010_2", to_base=5))  # "2040_5" 30 + 33 = 270

3. Find Minimum Valid Base

from BaseKit import minBase

print(minBase("Z"))  # 36 (max symbol in base-36)
print(minBase("1A"))  # 11 (symbol 'A' requires base ≥11)

Error Handling

Common Errors and Exceptions

Example Tests from tests.py:

# tests.py
from BaseKit import rebase


def test_error_handling(self):
    with self.assertRaises(ValueError):  # Error.DigitInvalidForBase
        rebase("G_16")
    with self.assertRaises(SyntaxError):  # Error.NoBaseGiven
        rebase("1011")
    with self.assertRaises(ValueError):  # Error.BelongingToBase
        rebase("3.14_10", to_base=37)

Testing

Run unit tests to verify functionality:

python -m unittest tests.py -v

Test Coverage:

• Conversions: Integers, fractions, edge cases (e.g., 0_10 -> 0_2).
• Expressions: Mixed-base operations, parentheses, error propagation.
• Errors: Invalid digits, missing bases, out-of-range bases.

Notes

• Precision: Fractional results are truncated to 10 decimal places.
• Security: Uses eval() internally. Avoid untrusted input.
• Alphabet: Default: 0-9, A-Z (case-insensitive). Extend via abc parameter.

Author: Fedor Tyulpin
Version: 1.0