test_fourier.py 文件源码

def test_LLinv(adjcube):
    """Tests L and its inverse.
    """
    from pydft.bases.fourier import L, Linv
    Sprod = np.prod(adjcube.S)
    for i in range(10):
        v = np.random.random(size=Sprod)
        #Our v is real; but due to round-off problems, there will be
        #tiny imaginary values. Chop them off. We only keep the last
        #N-1 components because the 0 component is NaN.
        it = Linv(L(v))[1:]
        if abs(np.max(np.imag(it))) < 1e-14:
            it = np.real(it)
        assert np.allclose(it, v[1:])