How to use the aotools.fouriertransform function in aotools

def test_ft():
    data = numpy.random.random((100))
    ft_data = fouriertransform.ft(data, 0.1)
    assert ft_data.shape == data.shape

def test_rft():
    data = numpy.zeros((100))
    data_width = len(data)
    rft_data = fouriertransform.rft(data, 1.)
    width, = rft_data.shape
    rescaled_width = (width-1)*2
    assert rescaled_width == data_width

#Observation Plane Co-ords
    x2,y2 = numpy.meshgrid( outputSpacing*numpy.arange(-N/2,N/2),
                            outputSpacing*numpy.arange(-N/2,N/2) )
    r2sq = x2**2 + y2**2

    #Quadratic phase factors
    Q1 = numpy.exp( 1j * k/2. * (1-mag)/z * r1sq)

    Q2 = numpy.exp(-1j * numpy.pi**2 * 2 * z/mag/k*fsq)

    Q3 = numpy.exp(1j * k/2. * (mag-1)/(mag*z) * r2sq)

    #Compute propagated field
    outputComplexAmp = Q3 * fouriertransform.ift2(
                    Q2 * fouriertransform.ft2(Q1 * inputComplexAmp/mag,inputSpacing), df1)
    return outputComplexAmp

#Evaluate Fresnel-Kirchhoff integral
    A = 1./(1j * wvl * Dz1)
    B = numpy.exp(1j * k/(2*Dz1) * (x1a**2 + y1a**2) )
    C = fouriertransform.ft2(Uin * numpy.exp(1j * k/(2*Dz1) * (x1**2 + y1**2)), d1)
    Uitm = A*B*C
    #Observation plane
    Dz2 = z - Dz1

    #coordinates
    x2,y2 = numpy.meshgrid( numpy.arange(-N/2., N/2.) * d2,
                            numpy.arange(-N/2., N/2.) * d2 )

    #Evaluate the Fresnel diffraction integral
    A = 1. / (1j * wvl * Dz2)
    B = numpy.exp( 1j * k/(2 * Dz2) * (x2**2 + y2**2) )
    C = fouriertransform.ft2(Uitm * numpy.exp( 1j * k/(2*Dz2) * (x1a**2 + y1a**2)), d1a)
    Uout = A*B*C

    return Uout