Find a prime #?

[Strob]

You can maybe find inspiration on wikipedia, there are a lot of information on them there:

in particular this article about how to find prime number in a list:
http://en.wikipedia.org/wiki/Sieve_of_Eratosthenes

[Eric-Harvey]

The best (and possibly only) way to find primes is to run through the numbers and see if they divisable by anything other than 1 and themselves. A good function to help with this in max is Mod. Mod returns the remainder of 2 numbers when they are divided. If the remainder is 0 then the second number is a multiple of the first. Here is a sample script, hope this is clear.

primeAr = #() --empty array for storing primes
for x = 2 to 100 do --count of the numbers to be checked for primality
(
divisible = false --variable for storing whether or not a divisor is found
for y = 2 to (x-1) do --count of numbers to check against original number (1 and the number itself are not included)
(
if (mod x y) == 0 then divisible = true --checks remainder and determines if x can be divided by y
)
if divisible == false then append PrimeAr x --if x can not be divided by y then it is a prime number
)
primeAr

[Jsnyder]

Thanks Eric! That's great haha, seems like a simple answer like i figured it would be.

[Strob]

I also found this page where someone talks about a python script to determine if a number is prime:

http://krenzel.info/?p=83

Cause it seems that trying to find if a number is prime is more useful than listing all the primes.

[Strob]

I also just found that if you want to print more than 20 elements of the array, you need to use this:

with printAllElements on primeAr as string

If you just write primeAr, you can only see the 20 first prime numbers.

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