fftlog-lss 0.1.0

JAX-accelerated FFTLog implementation for Large Scale Structure cosmology

FFTLog

A Python implementation of FFTLog for fast logarithmic FFT transforms, developed for PyBird.

Installation

From PyPI (recommended)

pip install fftlog-lss

From source

git clone https://github.com/pierrexyz/fftlog.git
cd fftlog
pip install --editable .

Dependencies

• Python >= 3.8
• numpy >= 1.20.0
• scipy >= 1.7.0

Usage

FFTLog provides fast logarithmic FFT transforms for scientific computing applications. Here's a basic example:

import numpy as np
from fftlog import FFTLog

# Initialize FFTLog
fftlog = FFTLog(
    Nmax=1024,      # Number of points
    xmin=1e-3,      # Minimum x value
    xmax=1e3,       # Maximum x value
    bias=0.0,       # Bias parameter
    complex=False   # Use real FFT
)

# Example function
x = np.logspace(-3, 3, 1000)
f = np.exp(-x**2)  # Gaussian function

# Transform
result = fftlog.rec(x, f)

Features

• Fast logarithmic FFT transforms
• Support for both real and complex transforms
• Spherical Bessel transforms
• Anti-aliasing windows
• Optimized for Large Scale Structure cosmology

Documentation

For more detailed examples and documentation, see the notebooks in the notebooks/ directory.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.