#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""Fast Fourier Transform (FFT) library container"""
import scipy.fft
from types import ModuleType
from typing import Optional
from ..util.decorators import deprecated
__all__ = ["get_fftlib", "set_fftlib"]
# Object to hold FFT interfaces
__FFTLIB: Optional[ModuleType] = scipy.fft
@deprecated(version="0.11.0", version_removed="1.0")
def set_fftlib(lib: Optional[ModuleType] = None) -> None:
"""Set the FFT library used by librosa.
.. warning:: This functionality is deprecated in librosa 0.11 and will be
removed in 1.0. To achieve the same effect, use either the
`scipy.fft.set_backend` context manager or
`scipy.fft.set_global_backend` function.
Parameters
----------
lib : None or module
Must implement an interface compatible with `scipy.fft`.
If ``None``, reverts to `scipy.fft`.
Examples
--------
Use `pyfftw`:
>>> import pyfftw
>>> librosa.set_fftlib(pyfftw.interfaces.numpy_fft)
Reset to default `scipy` implementation
>>> librosa.set_fftlib()
"""
global __FFTLIB
if lib is None:
lib = scipy.fft
__FFTLIB = lib
def get_fftlib() -> ModuleType:
"""Get the FFT library currently used by librosa
Returns
-------
fft : module
The FFT library currently used by librosa.
Must API-compatible with `numpy.fft`.
"""
if __FFTLIB is None:
# This path should never occur because importing
# this module will call set_fftlib
assert False # pragma: no cover
return __FFTLIB