sunburst-bayes 1.0.0

GPU-accelerated Bayesian evidence calculation via radial shooting techniques

SunBURST

Seeded Universe Navigation — Bayesian Unification via Radial Shooting Techniques

A GPU-accelerated Bayesian evidence calculator achieving machine-precision accuracy through 1024 dimensions with sub-linear scaling.

Features

• Extreme scalability: O(D^0.67) scaling vs O(exp(D)) for traditional methods
• GPU acceleration: 1000× speedup over dynesty/PolyChord at matched dimensions
• High dimensions: Works reliably from 2D to 1024D+
• Pure Python: No compilation required, NumPy/CuPy compatible
• Automatic mode detection: Handles multimodal posteriors automatically

Installation

pip install sunburst

For GPU acceleration (optional but recommended):

pip install cupy-cuda11x  # For CUDA 11.x
# or
pip install cupy-cuda12x  # For CUDA 12.x

Quick Start

import numpy as np
from sunburst import compute_evidence

# Define your log-likelihood (must handle batched inputs)
def log_likelihood(x):
    x = np.atleast_2d(x)
    return -0.5 * np.sum(x**2, axis=1)  # Gaussian

# Define parameter bounds
dim = 64
bounds = [(-10, 10)] * dim

# Compute evidence
result = compute_evidence(log_likelihood, bounds)

print(f"log Z = {result.log_evidence:.4f} ± {result.log_evidence_std:.4f}")
print(f"Peaks found: {result.n_peaks}")
print(f"Time: {result.wall_time:.2f}s")

Performance Benchmarks

Tested on RTX 3080 Laptop GPU with n_oscillations=1:

Dimension	SunBURST	dynesty	UltraNest	Speedup
2D	0.39s	0.61s	0.87s	1.6-2.2×
8D	0.42s	37s	54s	88-129×
64D	0.71s	TIMEOUT	TIMEOUT	>1200×
256D	2.72s	—	—	∞
1024D	14.0s	—	—	∞

TIMEOUT = >600s (10 minutes)

SunBURST completes in seconds where traditional methods timeout.

Built-in Test

Verify your installation:

import sunburst
result = sunburst.test(dim=64)  # Runs Gaussian benchmark

Or from command line:

sunburst --test gaussian --dim 64

Configuration Options

result = compute_evidence(
    log_likelihood,
    bounds,
    n_oscillations=1,     # 1=fast, 3=conservative mode detection
    fast=True,            # Fast Hessian estimation
    return_peaks=True,    # Include peak locations in result
    verbose=False,        # Suppress progress output
    seed=42,              # Reproducibility
)

Result Object

result.log_evidence        # float: Estimated log Z
result.log_evidence_std    # float: Uncertainty estimate
result.n_peaks             # int: Number of modes found
result.peaks               # ndarray: (n_peaks, dim) peak locations
result.hessians            # list: Hessian matrices at peaks
result.log_evidence_per_peak  # ndarray: Evidence contribution per peak
result.wall_time           # float: Total computation time
result.module_times        # dict: Per-stage timing breakdown
result.n_likelihood_calls  # int: Total likelihood evaluations
result.config              # dict: Configuration used

GPU Utilities

from sunburst import gpu_available, gpu_info, get_array_module

if gpu_available():
    print(gpu_info())
    xp = get_array_module()  # Returns cupy if available, else numpy

Architecture

SunBURST uses a 4-stage pipeline, named after Guang Ping Yang Style Tai Chi forms:

1. CarryTiger (抱虎歸山): Mode detection via ray casting
2. GreenDragon (青龍出水): Peak refinement with L-BFGS
3. BendTheBow (彎弓射虎): Evidence calculation via Laplace approximation
4. GraspBirdsTail (攬雀尾): Optional dimensional reduction

Citation

If you use SunBURST in your research, please cite:

@software{sunburst,
  author = {Wolfson, Ira},
  title = {SunBURST: GPU-accelerated Bayesian Evidence Calculation},
  year = {2026},
  url = {https://github.com/beastraban/sunburst}
}

License

MIT License — see LICENSE for details.

Contributing

Contributions welcome! Please see our contributing guidelines.

Acknowledgments

Module names honor Master Donald Rubbo and the Guang Ping Yang Style Tai Chi (廣平楊式太極拳) tradition.