Question

So I've been working on assignment two, and though I get no syntax error, when I run the program there is no output, so there must be something wrong with my logic here. Anyone mind checking it?

http://dpaste.com/675856/

Answer 1

Now that I look at it again, I'm assuming the problem is that no divisor will cause the remainder to be 1 other than the original number, so there can be no output. I'm guessing that my divisor has to be a combination of two different odd numbers. Not sure how I'll get that to happen yet though.

Answer 2

if (oddNum%divisor == 1): should be if (oddNum%divisor == 0): I guess

Answer 3

Yeah thanks! I actually realized that after I responded to myself, and fixed that, but it still isn't creating output. I'm assuming its stuck in an infinite loop in some way,

Answer 4

You are in a infinite loop, you don't increment the value of divisor: divisor - 1 instead of divisor = divisor -1. And then you have still some logical failures ;-)
But you will find them. It helps if you put print statements of values in your code, so you see the progression and how your values change (or not)

Answer 5

Oh didn't realize that was necessary. Thanks for all the help! Will try and figure out what's going wrong.

Answer 6

No worries, keep trying. Asking questions is free ;-)

Answer 7

Alright, so I followed your advice and realized that I was actually finding all numbers that weren't prime by my method, haha. So what I'm trying to do now is actually use a for loop to create a list of possible divisors. The problem I am having is finding a way such that it will try all points between the number 2 and the oddNum before printing that it's prime, rather than saying its prime after each individual divisor test. Any idea which way I Should go with this?

Answer 8

If it helps here is my new code: http://dpaste.com/676869/

I know the problem is with the if statement I just can't think of a way to fix it. Is it even changing divisor from 2 at all or is it keeping oddNum steady at 3 for all the tests because that's where it's initialized at the beginning?

Answer 9

"It is set to 998 because 1 and 2 are untested primes, as oddNum is initially set to 3."

1 is not a prime number ^^
You need a loop within a loop; one loop to increment the prime candidates, and one to increment the numbers that you're testing as divisors.

You can see my implementation at http://meeplikesheep.wordpress.com/2011/12/23/237/ , but everybody has their own way of coding, and it's more fun to work it out yourself and then compare. Good luck!