import pytest from pathlib import Path import numpy as np from numpy.testing import assert_allclose from optifik.fft import thickness_from_fft from optifik.analysis import smooth_intensities from optifik.io import load_spectrum @pytest.fixture def test_data_dir(): return Path(__file__).parent.parent / 'data' def test_FFT(test_data_dir): spectrum_path = test_data_dir / 'basic' / '003582.xy' expected = 3524.51 lambdas, raw_intensities = load_spectrum(spectrum_path, wavelength_min=450) smoothed_intensities = smooth_intensities(raw_intensities) r_index = 1.324188 + 3102.060378 / (lambdas**2) thickness_FFT = thickness_from_fft(lambdas, smoothed_intensities, refractive_index=r_index) result = thickness_FFT.thickness assert_allclose(result, expected, rtol=1e-1)