esinxe Random Number Generator

esinxe is a deterministic, random-access number generator for Python, C#, C++, C, Ruby, JavaScript/TypeScript, Rust, Go, Java, and Kotlin.

Version 1.0.1

Author: Danny Ward

The original idea was to generate value y directly from key x, instead of advancing a generator through every previous value. That is still the design: NextAt(n) computes the nth value from the current seed immediately, which is useful for procedural generation, chunked worlds, repeatable simulations, and other cases where you need stable randomness at an arbitrary coordinate.

This version replaces the old floating-point e^sin(x^e) prototype with a 64-bit integer mixing function. That makes the generator deterministic across languages, avoids floating-point drift, and gives a much healthier distribution for practical non-cryptographic use.

This is not a cryptographic random number generator. Do not use it for passwords, tokens, key generation, gambling, or security-sensitive decisions.

See docs/RNG_ANALYSIS.md for a more detailed discussion of what this generator is and is not useful for.

API

• SetSeed(seed) resets the seed and sequence index.
• Next() returns the next value and advances the sequence.
• NextAt(offset) returns the value at offset without advancing.
• NextRaw() returns the next raw 64-bit value and advances the sequence.
• NextRawAt(offset) returns the raw 64-bit value at offset.
• NextMax(maxvalue) returns 0 <= value < maxvalue.
• NextMaxAt(offset, maxvalue) returns 0 <= value < maxvalue.
• NextMinMax(minvalue, maxvalue) returns minvalue <= value < maxvalue.
• NextMinMaxAt(offset, minvalue, maxvalue) returns a ranged value at offset.
• List/array helpers return consecutive values and advance when no explicit offset is supplied.

Testing

Run the included smoke and statistical tests with:

python3 -m unittest discover -s tests

Or run the full local CI check:

./scripts/ci.sh

Run the local performance benchmark with:

python3 setup.py build_ext --inplace
python3 scripts/benchmark.py

Python package

The Python implementation can be installed locally:

python3 -m pip install -e .

Then import it with:

import esinxe

rng = esinxe.Random(12345)
print(rng.NextAt(1000))

The historical Python/Esinxepy1-0-0.py file remains as a compatibility shim.

Language implementations

• Python/ and src/esinxe/: Python package and legacy shim.
• C/: C header implementation.
• C++/: C++ header implementation.
• C#/: C# implementation.
• Ruby/: Ruby implementation.
• JavaScript/: JavaScript implementation with TypeScript declarations.
• Rust/: Rust crate.
• Go/: Go module.
• JVM/java/: Java implementation and smoke test.
• JVM/kotlin/: Kotlin implementation and smoke test.

All ports are expected to match tests/vectors.json.

To build publishable Python artifacts:

python3 -m build
python3 -m twine check dist/*