Source code for taxcalc.consumption
"""
Tax-Calculator Consumption class.
"""
# CODING-STYLE CHECKS:
# pycodestyle consumption.py
# pylint --disable=locally-disabled consumption.py
import os
from taxcalc.parameters import Parameters
from taxcalc.policy import Policy
from taxcalc.records import Records
[docs]
class Consumption(Parameters):
"""
Consumption is a subclass of the abstract Parameters class, and
therefore, inherits its methods (none of which are shown here).
Constructor for Consumption class.
Parameters
----------
none
Returns
-------
class instance: Consumption
"""
JSON_START_YEAR = Policy.JSON_START_YEAR
DEFAULT_NUM_YEARS = Policy.DEFAULT_NUM_YEARS
DEFAULTS_FILE_NAME = 'consumption.json'
DEFAULTS_FILE_PATH = os.path.abspath(os.path.dirname(__file__))
def __init__(self):
super().__init__()
self.initialize(Consumption.JSON_START_YEAR,
Consumption.DEFAULT_NUM_YEARS)
[docs]
@staticmethod
def read_json_update(obj):
"""
Return a revision dictionary suitable for use with update_consumption
method derived from the specified JSON object, which can be None or
a string containing a local filename, a URL beginning with 'http'
pointing to a valid JSON file hosted online, or a valid JSON text.
"""
return Parameters._read_json_revision(obj, 'consumption')
[docs]
def update_consumption(self, revision,
print_warnings=True, raise_errors=True):
"""
Update consumption default values using specified revision dictionary.
See Parameters._update for argument documentation and details about
the expected structure of the revision dictionary.
"""
self._update(revision, print_warnings, raise_errors)
RESPONSE_VARS = set(['e17500', 'e18400', 'e19800', 'e20400'])
BENEFIT_VARS = set(['housing', 'snap', 'tanf', 'vet', 'wic',
'mcare', 'mcaid', 'other'])
[docs]
def has_response(self):
"""
Return true if any MPC parameters are positive for current_year or
if any BEN value parameters are less than one for current_year;
return false if all MPC parameters are zero and all BEN value
parameters are one
"""
for var in Consumption.RESPONSE_VARS:
if getattr(self, 'MPC_{}'.format(var)) > 0.0:
return True
for var in Consumption.BENEFIT_VARS:
if getattr(self, 'BEN_{}_value'.format(var)) < 1.0:
return True
return False
[docs]
def response(self, records, income_change):
"""
Changes consumption-related records variables given income_change
and the current values of the MPC consumption parameters
"""
if not isinstance(records, Records):
raise ValueError('records is not a Records object')
for var in Consumption.RESPONSE_VARS:
records_var = getattr(records, var)
mpc_var = getattr(self, 'MPC_{}'.format(var))
records_var[:] += mpc_var * income_change
[docs]
def benval_params(self):
"""
Returns list of BEN_*_value parameter values
"""
return [getattr(self, 'BEN_{}_value'.format(var))
for var in Consumption.BENEFIT_VARS]