#F.py, exer 7.1
from math import exp, sin, pi

class F:
    def __init__(self, a, w):
        self.a = a
        self.w = w

    def value(self,x):
        return exp(-self.a*x)*sin(self.w*x)

#create two instances (objects) of class F
f1 = F(1.0,0.1)
f2 = F(2.0,0.1)

#print the coefficient a from both objects
print(f1.a,f2.a)

#evaluate and print both for x = pi

print(f1.value(pi))
print(f2.value(pi))

"""
Terminal > python F.py
1.0 2.0
0.01335383513703555
0.0005770715401197441
"""