def net_present_value(self, ini_year, end_year, val_years):
"""
Compute net present value between present year and future year.
Parameters
----------
ini_year: float
initial year
end_year: float
end year
val_years: np.array
cash flow at each year btw ini_year and end_year (both included)
Returns
-------
net_present_value: float
net present value between present year and future year.
"""
year_range = np.arange(ini_year, end_year + 1)
if year_range.size != val_years.size:
raise ValueError('Wrong size of yearly values.')
sel_disc = self.select(year_range)
if sel_disc is None:
raise ValueError('No information of discount rates for provided years:'
f' {ini_year} - {end_year}')
return u_fin.net_present_value(sel_disc.years, sel_disc.rates,
val_years)
def test_net_pres_val_pass(self):
""" Test net_present_value against MATLAB reference"""
years = np.arange(2018, 2041)
disc_rates = np.ones(years.size)*0.02
val_years = np.ones(years.size)*6.512201157564418e9
res = net_present_value(years, disc_rates, val_years)
self.assertEqual(1.215049630691397e+11, res)
def net_present_value(self, ini_year, end_year, val_years):
"""Compute net present value between present year and future year.
Parameters:
ini_year (float): initial year
end_year (float): end year
val_years (np.array): cash flow at each year btw ini_year and
end_year (both included)
Returns:
float
"""
year_range = np.arange(ini_year, end_year + 1)
if year_range.size != val_years.size:
LOGGER.error('Wrong size of yearly values.')
raise ValueError
sel_disc = self.select(year_range)
if sel_disc is None:
LOGGER.error('No information of discount rates for provided years:'\
' %s - %s', ini_year, end_year)
raise ValueError
return u_fin.net_present_value(sel_disc.years, sel_disc.rates,
val_years)
