evobench-lib 1.0.0

A comprehensive benchmarking suite for evolutionary algorithms and metaheuristics with built-in statistical analysis and visualization

evolutionary-benchmarking

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Overview

evobench is a lightweight, standards-based library for benchmarking evolutionary algorithms and metaheuristics. It addresses the critical gap in scientific rigor when validating custom algorithm implementations by providing:

• Native baseline implementations of industry-standard metaheuristics (EDA, PSO, ABC)
• Automated experiment orchestration over classical continuous optimization benchmarks
• Rigorous statistical analysis tools for hypothesis testing and convergence evaluation
• Reproducibility guarantees through standardized experimental protocols

Whether you're developing a novel evolutionary strategy or comparing existing methods, evobench ensures your experimental results are scientifically sound, statistically valid, and directly comparable across different implementations.

Why evobench?

The scientific literature on evolutionary computation suffers from inconsistencies in experimental methodology:

• Different research groups use different benchmark functions with varying dimensionalities
• Hyperparameter configurations are often incompletely specified
• Statistical significance is rarely established through rigorous testing
• Convergence behavior is rarely analyzed beyond point estimates

evobench eliminates these issues by enforcing standardized experimental protocols, enabling the global research community to perform fair algorithmic comparisons.

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Key Features

Standardized Benchmarking

• Classical continuous optimization functions (Ackley, Rosenbrock, Sphere, Schwefel 1.2, Trid)
• Configurable problem dimensions and search space bounds
• Deterministic initialization and reproducible random number generation

Native Algorithm Baseline

• Estimation of Distribution Algorithm (EDA): probabilistic model-based search
• Particle Swarm Optimization (PSO): velocity-based population dynamics
• Artificial Bee Colony (ABC): swarm intelligence with three behavioral phases
• All implementations fully vectorized with NumPy for computational efficiency

Experiment Engine

• Single configuration dictionary for complex multi-algorithm, multi-benchmark studies
• Automatic execution of independent runs with timing and convergence tracking
• JSON-based result persistence for post-hoc analysis
• System metadata capture for reproducibility

Statistical Analysis

• Fitness vector extraction and organization for arbitrary algorithm combinations
• Parametric (ANOVA) and non-parametric (Kruskal-Wallis) significance testing
• Colored ANSI reporting with dynamic α support for customized significance levels
• Convergence curve visualization and statistical reporting
• Effect size computation (Cohen's d) for practical significance assessment

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Installation

From PyPI (Recommended)

pip install evobench-lib

From Source

git clone https://github.com/NewtonGomez/evolutionary-benchmarking.git
cd evobench
pip install -e .

Requirements

• Python 3.8+
• NumPy >= 1.19.0
• SciPy >= 1.5.0 (for statistical tests)

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Quickstart

1. Define Your Custom Algorithm

Create a class inheriting from EvolutionaryAlgorithm:

import numpy as np
from evobench.base import EvolutionaryAlgorithm

class MyCustomAlgorithm(EvolutionaryAlgorithm):
    """
    A simple evolutionary strategy for demonstration.
    """
    def __init__(self, objective_function, bounds, population_size=50, 
                 max_iterations=100, learning_rate=0.1):
        super().__init__(objective_function, bounds, population_size, max_iterations)
        self.learning_rate = learning_rate
    
    def run(self):
        """Execute the custom algorithm."""
        population = self._initialize_population()
        
        for generation in range(self.max_iterations):
            # Evaluate fitness
            fitness_values = np.array([
                self.objective_function(ind) for ind in population
            ])
            
            # Track best solution
            best_idx = np.argmin(fitness_values)
            if fitness_values[best_idx] < self.best_fitness:
                self.best_individual = population[best_idx].copy()
                self.best_fitness = fitness_values[best_idx]
            
            self.fitness_history.append(self.best_fitness)
            
            # Simple update: move towards best solution
            best_solution = population[best_idx]
            population += self.learning_rate * (best_solution - population)
            
            # Enforce boundaries
            lower_bounds = self.bounds[:, 0]
            upper_bounds = self.bounds[:, 1]
            population = np.clip(population, lower_bounds, upper_bounds)
        
        return self.best_individual, self.best_fitness

2. Configure and Run Experiments

import numpy as np
from evobench.benchmarks import sphere, ackley
from evobench.algorithms import PSO, EDA, ABC
from evobench.tools.experiment_engine import run_automated_experiment
from my_algorithm import MyCustomAlgorithm

# Define experiment configuration
experiment_config = {
    "dimensions": 10,
    "population_size": 50,
    "max_iterations": 100,
    "independent_runs": 20,  # 20 independent trials per algorithm-benchmark pair
    
    "benchmarks": [
        {
            "name": "Sphere",
            "func": sphere,
            "bounds": [[-600, 600]] * 10
        },
        {
            "name": "Ackley",
            "func": ackley,
            "bounds": [[-10, 10]] * 10
        }
    ],
    
    "algorithms": [
        {
            "name": "PSO",
            "class": PSO,
            "params": {"inertia_weight": 0.7, "cognitive_coeff": 1.5, "social_coeff": 1.5}
        },
        {
            "name": "EDA",
            "class": EDA,
            "params": {"elite_fraction": 0.2, "variance_fraction": 0.1}
        },
        {
            "name": "ABC",
            "class": ABC,
            "params": {"limit": 50}
        },
        {
            "name": "Custom Algorithm",
            "class": MyCustomAlgorithm,
            "params": {"learning_rate": 0.05}
        }
    ]
}

# Execute the experiment
run_automated_experiment(experiment_config, output_file="results.json")

3. Analyze Results Statistically

from evobench.tools.experiment_engine import unpack_fitness_results
from evobench.stats import analyze, stat_report

# Load experimental results and extract fitness vectors for a specific benchmark
fitness_dict = unpack_fitness_results("results.json", "Sphere")
# Extract the algorithm names and their corresponding fitness arrays.
algo_names = list(fitness_dict.keys())
fitness_data = list(fitness_dict.values())
# Run the statistical analysis.
# The 'analyze' function will calculate descriptive stats, run normality checks, 
# and execute the appropriate hypothesis test. You can optionally adjust 'alpha' (default: 0.05).
result_dict = analyze("Sphere Function (10D)", fitness_data, algo_names, alpha=0.05)
# Print the beautifully formatted, color-coded performance report (ANSI colors).
stat_report(result_dict)

Output:

Algorithm Performance on Sphere Function 
============================================================

PSO:
  Mean fitness:     1.24e-02
  Std deviation:    8.63e-03
  Best result:      2.41e-03

EDA:
  Mean fitness:     3.15e-02
  Std deviation:    1.92e-02
  Best result:      8.77e-03

ABC:
  Mean fitness:     2.87e-02
  Std deviation:    1.54e-02
  Best result:      6.23e-03

Custom Algorithm:
  Mean fitness:     5.42e-02
  Std deviation:    3.21e-02
  Best result:      1.52e-02

============================================================
ANOVA Test Results:
  F-statistic:      18.523
  p-value:          2.31e-10
  Significant:      Yes (α=0.05)

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Project Structure

evobench/
├── src/evobench/
│   ├── __init__.py                # Facade: exposes main APIs
│   ├── base.py                    # Abstract base class for evolutionary algorithms
│   ├── algorithms/
│   │   ├── __init__.py            # Facade: PSO, EDA, ABC
│   │   ├── eda.py                 # Estimation of Distribution Algorithm
│   │   ├── pso.py                 # Particle Swarm Optimization
│   │   └── bee.py                 # Artificial Bee Colony
│   ├── benchmarks/                # Benchmark function modules
│   │   ├── __init__.py            # Facade: sphere, ackley, rosenbrock, schwefel, trid
│   │   ├── unimodal.py            # Unimodal functions (sphere, rosenbrock, schwefel, trid)
│   │   └── multimodal.py          # Multimodal functions (ackley)
│   ├── stats/                     # Statistical analysis tools
│   │   ├── __init__.py            # Facade: analyze, stat_report
│   │   ├── core_test.py           # Normality and hypothesis tests
│   │   ├── reporter.py            # Colored ANSI reporting
│   │   └── analyzer.py            # Fitness data analysis
│   └── tools/
│       ├── __init__.py
│       ├── operators.py           # Genetic operators (selection, crossover, mutation)
│       └── experiment_engine.py   # Automated experiment orchestration
├── tests/
│   ├── __init__.py
│   ├── test_base.py              # Unit tests for base class
│   ├── test_operators.py         # Operator validation
│   └── test_benchmarks.py        # Benchmark function correctness
├── docs/                          # Sphinx/MkDocs documentation
├── README.md
├── LICENSE
├── pyproject.toml
└── CONTRIBUTING.md

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Usage Patterns

Pattern 1: Comparing Two Algorithms on a Single Benchmark

To see all the benchmark functions, click here.

from evobench.algorithms import PSO, ABC
from evobench.benchmarks import rosenbrock
from evobench.tools.experiment_engine import run_automated_experiment

config = {
    "dimensions": 5,
    "population_size": 30,
    "max_iterations": 50,
    "independent_runs": 10,
    "benchmarks": [
        {
            "name": "Rosenbrock",
            "func": rosenbrock,
            "bounds": [[-10, 10]] * 5
        }
    ],
    "algorithms": [
        {"name": "PSO", "class": PSO, "params": {}},
        {"name": "ABC", "class": ABC, "params": {}}
    ]
}

run_automated_experiment(config)

Pattern 2: Parameter Sensitivity Analysis

# Test how PSO performance varies with inertia weight
inertia_weights = [0.5, 0.7, 0.9]

for w in inertia_weights:
    config = {
        "dimensions": 10,
        "population_size": 50,
        "max_iterations": 100,
        "independent_runs": 15,
        "benchmarks": [...],
        "algorithms": [
            {
                "name": f"PSO (w={w})",
                "class": PSO,
                "params": {"inertia_weight": w}
            }
        ]
    }
    run_automated_experiment(config, output_file=f"pso_sensitivity_w{w}.json")

Pattern 3: Validating Custom Algorithm Implementation

from evobench.algorithms import PSO
from my_algorithms import MyNovelAlgorithm

# Test that your algorithm performs at least comparably to known baseline
config = {
    "dimensions": 10,
    "population_size": 50,
    "max_iterations": 100,
    "independent_runs": 30,  # Higher number for statistical power
    "benchmarks": [
        {"name": "Sphere", "func": sphere_function, "bounds": [[-600, 600]] * 10},
        {"name": "Ackley", "func": ackley_function, "bounds": [[-10, 10]] * 10},
    ],
    "algorithms": [
        {"name": "PSO Baseline", "class": PSO, "params": {}},
        {"name": "My Algorithm", "class": MyNovelAlgorithm, "params": {}}
    ]
}

run_automated_experiment(config, output_file="validation_results.json")

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API Reference

Core Classes

EvolutionaryAlgorithm (Abstract Base Class)

All algorithms must inherit from this class:

class EvolutionaryAlgorithm(ABC):
    def __init__(self, objective_function: Callable, bounds: List, 
                 population_size: int = 50, max_iterations: int = 100):
        """Initialize the algorithm with common parameters."""
        
    @abstractmethod
    def run(self) -> Tuple[np.ndarray, float]:
        """Execute the algorithm and return best solution and fitness."""

Benchmark Functions

All functions have signature fn(x: np.ndarray) -> float:

• sphere(x): Convex, unimodal baseline
• rosenbrock(x): Non-convex valley topology
• ackley(x): Multimodal with shallow exterior
• schwefel(x): Non-separable, quadratic
• trid(x): Highly interdependent variables

Experiment Engine

run_automated_experiment(config: Dict[str, Any], 
                        output_file: str = "results.json") -> None:
    """Execute a full benchmark experiment."""

unpack_fitness_results(json_path: str, 
                       target_function: str) -> Dict[str, np.ndarray]:
    """Extract and organize fitness vectors from results JSON."""

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Contributing

Contributions are welcome! Please see CONTRIBUTING.md for guidelines on:

• Code style (PEP 8)
• Testing requirements
• Documentation standards
• Pull request process

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Citation

If you use evobench in your research, please cite:

@software{evobench2026,
  title={evobench: Standardized Benchmarking for Evolutionary Algorithms},
  author={Gómez, Enrique and Galván, Victoria},
  year={2026},
  url={https://github.com/NewtonGomez/evolutionary-benchmarking}
}

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Known Limitations

• Current implementation focuses on continuous optimization only (no discrete/combinatorial problems)
• Benchmark functions are limited to 1000-dimensional spaces for numerical stability
• Statistical tests currently assume normal distribution of fitness values
• DEAP integration and third-party operator libraries are planned for future releases

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License

This project is licensed under the GPL-3 License. See LICENSE file for details.

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Support

For bug reports and feature requests, please open an issue on GitHub.

For questions and discussions, visit our Discussions Forum.

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Acknowledgments

• NumPy and SciPy communities for foundational numerical computing tools
• Continuous optimization research community for standardized benchmark functions
• Academic advisors and collaborators who influenced the design philosophy

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Last Updated: April 2026
Version: 0.1.0
Authors:

• Enrique Gómez (GitHub, Email)
• Victoria Galván (GitHub, Email)