numpy.npv() in Python

numpy.npv(rate, value) : This financial function helps user to calculate the NPV(Net Present Value) of a cash flow series. 

Parameters : 

rate  : [scalar] Rate of discount 
value : [array_like, shape(M,)] value of 
        cash flows time series. The (fixed) time interval 
        between cash flow “events” must be the same as that
        for given rate is given. By convention, investments
        or “deposits” are -ve, income or “withdrawals” are +ve

Return : 

present value as per given parameters.

Equation being solved :

Code 1 : Working

Python

## Python program explaining npv() function
import numpy as np

#            rate            values
a =  np.npv(0.281,[-100, 19, 49, 58, 200])
print("Net Present Value(npv) : ", a)

Output : 

Net Present Value(npv) :  46.5579792365

References : https://docs.scipy.org/doc/numpy-1.13.0/reference/generated/numpy.npv.html .