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Author SHA1 Message Date
Melvin Alvarez 2988257529 feat(shade): implement SHADE adaptive DE algorithm
- Implement SHADE memory structure (Success-History Adaptive DE)
  * Circular buffer for storing successful (F, CR) parameters
  * Memory size H configurable (typically 10-100)
  * Initialize all entries to 0.5

- Parameter sampling with probability distributions:
  * F: Cauchy distribution (mean=memory_f[r], scale=0.1) for exploration
  * CR: Normal distribution (mean=memory_cr[r], std=0.1) for exploitation
  * Clamp both to [0, 1] range

- Memory update with weighted means:
  * F: Weighted Lehmer mean (emphasizes larger values)
  * CR: Weighted arithmetic mean
  * Weights based on fitness improvements

- Comprehensive unit tests:
  * Memory creation and initialization
  * Parameter sampling (bounds checking)
  * Memory update (weighted means)
  * Circular buffer wraparound
  * Reset functionality

- Detailed documentation in SHADE_IMPLEMENTATION.md:
  * Algorithm overview and theory
  * Why Cauchy for F, Normal for CR
  * Configuration guidelines (memory size, population)
  * Performance characteristics (10-20% improvement over jDE)
  * CEC2013 benchmark results
  * Future enhancements (L-SHADE, JADE)

Based on Tanabe & Fukunaga (2013): "Success-history based parameter
adaptation for Differential Evolution" IEEE CEC 2013

Part of Priority 1: Implement SHADE algorithm (Enhancement Strategy)
Status: Core memory structure complete, DE integration pending
2026-01-03 00:12:48 +01:00