def METHOD_NAME(kl, f):
    Xf = np.abs(kl - f)
    Xf = np.where(Xf == Xf.min())
    z1, z2, f1, f2 = (
        kl[int(Xf[0])][0],
        kl[int(Xf[0] - 1)][0],
        kl[int(Xf[0])][1],
        kl[int(Xf[0] - 1)][1],
    )
    z = z1 + ((z2 - z1) / (f2 - f1)) * (f - f1)
    return z