Question

Im on lecture 2 and cannot figure out how to separate odd numbers and prime numbers! I figured out how to generate odd numbers here http://dpaste.com/535600/ How do I get primes out of that?

Answer 1

Is there a specific interval of numbers that you want?

Answer 2

you want to put another loop in between line 6 and line 7 and it should be indented to the same level as line 6. that inner loop needs to test the number to see if it is prime

Answer 3

the new loop will be 'nested' 'inside' the 'outer' loop (the while loop)

Answer 4

How do I test it to see if it is a prime? Do I have to divide it by a number, etc lol im lost

Answer 5

A prime number evenly divides by itself and 1 ONLY. So n/n=1 & n/1=n. Both of these have remainder of 0. If n divided by any integer between 1 and n has a remainder of 0, then n is NOT prime. Use the modulus (%) operation to find if a number has a remainder. Ex. n=15. 15%2=1 (15/2= 7 with remainder of 1). 15%3=0 (15/3= 5 with remainder of 0). So since there is at least 1 divisor (besides 1 & 15), in this case, 3, that returns 0, then 15 is not a prime.

Answer 6

http://openstudy.com/updates/4db29a8764cb8b0b773f606e?source=email#/updates/4db692e6c08f8b0b3ee131c3

Check this question, it covers the same problem, there's a link to some working code that doesn't use imports or lists etc.. You might find what you need in there.

Answer 7

That link doesn't seem to work, should do? Erm, just go to the list of questions and it is currently the one at the very top. The title is

grupiyati: help with p1 anyone

Answer 8

http://pastebin.com/KU0CXFx3
There's a solution here if you wanted one.

Answer 9

https://gist.github.com/944461

This might help.

Answer 10

def is_prime(number):
if number < 2:
return False
for each in range(2, (number+2) / 2):
if number % each == 0:
return False
return True

tally, n = 0, 0
while tally < 1000:
n += 1
if is_prime(n):
tally += 1
print n
# modified and perfected by cs