def combine_tax_scales(
node: ParameterNodeAtInstant,
combined_tax_scales: typing.Optional[taxscales.MarginalRateTaxScale] = None,
) -> typing.Optional[taxscales.MarginalRateTaxScale]:
"""
Combine all the MarginalRateTaxScales in the node into a single
MarginalRateTaxScale.
"""
name = next(iter(node or []), None)
if name is None:
return combined_tax_scales
if combined_tax_scales is None:
combined_tax_scales = taxscales.MarginalRateTaxScale(name = name)
combined_tax_scales.add_bracket(0, 0)
for child_name in node:
child = node[child_name]
if isinstance(child, taxscales.MarginalRateTaxScale):
combined_tax_scales.add_tax_scale(child)
else:
log.info(
f"Skipping {child_name} with value {child} "
"because it is not a marginal rate tax scale",
)
return combined_tax_scales
def test_marginal_rates():
tax_base = numpy.array([0, 10, 50, 125, 250])
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(0, 0)
tax_scale.add_bracket(100, 0.1)
tax_scale.add_bracket(200, 0.2)
result = tax_scale.marginal_rates(tax_base)
tools.assert_near(result, [0, 0, 0, 0.1, 0.2])
def test_inverse():
gross_tax_base = numpy.array([1, 2, 3, 4, 5, 6])
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(0, 0)
tax_scale.add_bracket(1, 0)
tax_scale.add_bracket(3, 0)
net_tax_base = gross_tax_base - tax_scale.calc(gross_tax_base)
result = tax_scale.inverse()
tools.assert_near(result.calc(net_tax_base), gross_tax_base, 1e-15)
def test_scale_tax_scales():
tax_base = numpy.array([1, 2, 3])
tax_base_scale = 12.345
scaled_tax_base = tax_base * tax_base_scale
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(1, 0)
tax_scale.add_bracket(2, 0)
tax_scale.add_bracket(3, 0)
result = tax_scale.scale_tax_scales(tax_base_scale)
tools.assert_near(result.thresholds, scaled_tax_base)
def test_calc_without_round():
tax_base = numpy.array([200, 200.2, 200.002, 200.6, 200.006, 200.5, 200.005])
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(0, 0)
tax_scale.add_bracket(100, 0.1)
result = tax_scale.calc(tax_base)
tools.assert_near(
result,
[10, 10.02, 10.0002, 10.06, 10.0006, 10.05, 10.0005],
absolute_error_margin = 1e-10,
)
def test_calc_when_round_is_1():
tax_base = numpy.array([200, 200.2, 200.002, 200.6, 200.006, 200.5, 200.005])
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(0, 0)
tax_scale.add_bracket(100, 0.1)
result = tax_scale.calc(tax_base, round_base_decimals = 1)
tools.assert_near(
result,
[10, 10.0, 10.0, 10.1, 10.0, 10, 10.0],
absolute_error_margin = 1e-10,
)
def test_calc():
tax_base = numpy.array([1, 1.5, 2, 2.5, 3.0, 4.0])
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(0, 0)
tax_scale.add_bracket(1, 0.1)
tax_scale.add_bracket(2, 0.2)
tax_scale.add_bracket(3, 0)
result = tax_scale.calc(tax_base)
tools.assert_near(
result,
[0, 0.05, 0.1, 0.2, 0.3, 0.3],
absolute_error_margin = 1e-10,
)
def _get_at_instant(self, instant):
brackets = [
bracket.get_at_instant(instant) for bracket in self.brackets
]
if self.metadata.get('type') == 'single_amount':
scale = taxscales.SingleAmountTaxScale()
for bracket in brackets:
if 'amount' in bracket._children and 'threshold' in bracket._children:
amount = bracket.amount
threshold = bracket.threshold
scale.add_bracket(threshold, amount)
return scale
elif any('amount' in bracket._children for bracket in brackets):
scale = taxscales.MarginalAmountTaxScale()
for bracket in brackets:
if 'amount' in bracket._children and 'threshold' in bracket._children:
amount = bracket.amount
threshold = bracket.threshold
scale.add_bracket(threshold, amount)
return scale
elif any('average_rate' in bracket._children for bracket in brackets):
scale = taxscales.LinearAverageRateTaxScale()
for bracket in brackets:
if 'base' in bracket._children:
base = bracket.base
else:
base = 1.
if 'average_rate' in bracket._children and 'threshold' in bracket._children:
average_rate = bracket.average_rate
threshold = bracket.threshold
scale.add_bracket(threshold, average_rate * base)
return scale
else:
scale = taxscales.MarginalRateTaxScale()
for bracket in brackets:
if 'base' in bracket._children:
base = bracket.base
else:
base = 1.
if 'rate' in bracket._children and 'threshold' in bracket._children:
rate = bracket.rate
threshold = bracket.threshold
scale.add_bracket(threshold, rate * base)
return scale
def test_to_average():
tax_base = numpy.array([1, 1.5, 2, 2.5])
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(0, 0)
tax_scale.add_bracket(1, 0.1)
tax_scale.add_bracket(2, 0.2)
result = tax_scale.to_average()
# Note: assert_near doesn't work for inf.
assert result.thresholds == [0, 1, 2, numpy.inf]
assert result.rates, [0, 0, 0.05, 0.2]
tools.assert_near(
result.calc(tax_base),
[0, 0.0375, 0.1, 0.125],
absolute_error_margin = 1e-10,
)
def test_inverse_scaled_marginal_tax_scales():
gross_tax_base = numpy.array([1, 2, 3, 4, 5, 6])
gross_tax_base_scale = 12.345
scaled_gross_tax_base = gross_tax_base * gross_tax_base_scale
tax_scale = taxscales.MarginalRateTaxScale()
tax_scale.add_bracket(0, 0)
tax_scale.add_bracket(1, 0.1)
tax_scale.add_bracket(3, 0.05)
scaled_tax_scale = tax_scale.scale_tax_scales(gross_tax_base_scale)
scaled_net_tax_base = (
+ scaled_gross_tax_base
- scaled_tax_scale.calc(scaled_gross_tax_base)
)
result = scaled_tax_scale.inverse()
tools.assert_near(result.calc(scaled_net_tax_base), scaled_gross_tax_base, 1e-13)
def to_marginal(self) -> taxscales.MarginalRateTaxScale:
marginal_tax_scale = taxscales.MarginalRateTaxScale(
name = self.name,
option = self.option,
unit = self.unit,
)
previous_i = 0
previous_threshold = 0
for threshold, rate in zip(self.thresholds[1:], self.rates[1:]):
if threshold != float("Inf"):
i = rate * threshold
marginal_tax_scale.add_bracket(
previous_threshold,
(i - previous_i) / (threshold - previous_threshold),
)
previous_i = i
previous_threshold = threshold
marginal_tax_scale.add_bracket(previous_threshold, rate)
return marginal_tax_scale
