def test_inverse_marginal_tax_scale():
marginal_tax_scale = MarginalRateTaxScale()
marginal_tax_scale.add_bracket(0, 0)
marginal_tax_scale.add_bracket(1, 0.1)
marginal_tax_scale.add_bracket(3, 0.05)
brut = np.array([1, 2, 3, 4, 5, 3.28976, 8764])
net = brut - marginal_tax_scale.calc(brut)
inverse = marginal_tax_scale.inverse()
assert_near(brut, inverse.calc(net), 1e-15)
marginal_tax_scale.add_bracket(4, 0)
net = brut - marginal_tax_scale.calc(brut)
inverse = marginal_tax_scale.inverse()
assert_near(brut, inverse.calc(net), 1e-15)
def test_inverse_scaled_marginal_tax_scale():
marginal_tax_scale = MarginalRateTaxScale()
marginal_tax_scale.add_bracket(0, 0)
marginal_tax_scale.add_bracket(1, 0.1)
marginal_tax_scale.add_bracket(3, 0.05)
brut = np.array([1, 2, 3, 4, 5, 6])
net = brut - marginal_tax_scale.calc(brut)
inverse = marginal_tax_scale.inverse()
assert_near(brut, inverse.calc(net), 1e-15)
brut = np.array([1, 2, 3, 4, 5, 6])
brut_scale = 12.345
brut_scaled = brut * brut_scale
scaled_marginal_tax_scale = marginal_tax_scale.scale_tax_scales(brut_scale)
net_scaled = (brut_scaled - scaled_marginal_tax_scale.calc(brut_scaled))
scaled_inverse = scaled_marginal_tax_scale.inverse()
assert_near(brut_scaled, scaled_inverse.calc(net_scaled), 1e-13)
inverse = marginal_tax_scale.inverse()
inversed_net = inverse.calc(net)
net_scale = brut_scale
inversed_net_scaled = inversed_net * net_scale
assert_near(brut_scaled, inversed_net_scaled, 1e-13)
