taxtest.py

import sys

# The way this worksheet seems to work is:
# A = taxes you would pay if it was just income
# B = calculate taxes on capital gains, using the capital gains tax rate schedule, BUT skip the first X dollars of the rate schedule, where X is your income
# total taxes = A + B

def income_tax (amt):
	taxes = 0.0
	lower_end = 0
	brackets = [[18650, .1], [74900, .15], [153100, .25], [233350, .28], [416700, .33]]

	for bracket in brackets:
		taxable = min (amt, bracket[0]) - lower_end
		lower_end = bracket[0]
		taxes += max (taxable, 0) * bracket[1]
	
	return taxes


def calculate_worksheet (income, gain):
	line9 = min (74900., income + gain)
	line10 = min (income, line9)
	line11 = line9 - line10
	line12 = min (income + gain, gain)
	line13 = line9 - line10
	line14 = line12 - line13
	line16 = min (464850., income + gain)
	line17 = income + line11
	line18 = line16 - line17
	line19 = min (line14, line18)
	line20 = line19 * .15
	line21 = line11 + line19
	line22 = line12 - line21
	line23 = line22 * .2

	line25 = line20 + line23 + income_tax (income)
	line26 = income_tax (income + gain)

	#print line9
	#print line10
	#print line11
	#print line12
	#print line13
	#print line14
	#print line16
	#print line17
	#print line18
	#print line19
	#print line20
	#print line21
	#print line22
	#print line23
	#print line25
	#print line26

	return min (line25, line26)

def calculate_marginals (income, gain):
	tax_a = calculate_worksheet (income, gain)
	tax_b = calculate_worksheet (income + 1., gain)
	income_marginal = (tax_b - tax_a) / 1.

	tax_b = calculate_worksheet (income, gain + 1.)
	gains_marginal = (tax_b - tax_a) / 1.

	print "Taxes: ", tax_a
	print "Marginals: ", income_marginal, gains_marginal


income = int(sys.argv[1])
gain = int(sys.argv[2])

calculate_marginals (income, gain)
#print calculate_worksheet (income, gain)