Question

I am trying to make the exercise in python for week 2:
Write a program using a for loop that calculates exponentials. Your program should ask the user for a base base and an exponent exp, and calculate baseexp.

Any ideas? I cannot come up with the algorithm. I tried:

x=input("Give a base number:")
y=input("Give an exp number:")
if y>0:
for x in range(y):
x=x*x
y=y-1
else:
for x in range(y):
x=1/x*x
print x

But of course it is not working:)

Answer 1

base = 1
for i in range(y): # do it y times i takes the values 0,1,2,...(y-1),
....base = base * x # base = x then x*x then (x*x)*x then ...

Answer 2

A couple of things. First, don't use input() in Python 2.x. In Python 3.x it does what you want, but in Python 2 you use raw_input( "prompt string" )

Second, in your for loop when y > 0, you're iterating on y, and then changing y's value. Definite no-no. Test it in the interpreter printing out y's values, you'll see that it's a disaster.

Answer 3

Thanks a lot to both of you!