def METHOD_NAME(self):
    """Check body-centered cubic lattice."""
    l0 = 4
    m = l0 / 2
    xen = range(0, self.box_l, l0)
    for i, j, k in itertools.product(xen, repeat=3):
        self.system.part.add(type=self.part_ty, pos=(i, j, k))
        self.system.part.add(type=self.part_ty, pos=(i + m, j + m, k + m))
    wavevectors, intensities = self.system.analysis.structure_factor(
        sf_types=[self.part_ty], sf_order=self.sf_order)
    intensities = np.around(intensities, 8)
    np.testing.assert_array_equal(
        intensities[np.nonzero(intensities)], len(self.system.part))
    # reflection conditions
    # (h+k+l) even => F = 2f, otherwise F = 0
    peaks_ref = self.generate_peaks(
        l0, l0, l0, lambda h, k, l: (h + k + l) % 2 == 0)
    peaks = self.peak_orders(wavevectors[np.nonzero(intensities)])
    np.testing.assert_array_equal(peaks, peaks_ref[:len(peaks)])