How To Check Array For Prime Number?

[phpQuestioner]

How can I compare all prime numbers (number divisible by 3) in an array against against a variable in a if condition?

 

example

 

<?php
$checker = array("3","6","9","12","15");
if ($skip == in_array($checker))
{
// do something
}
?>

[rajivgonsalves]

use the "%" operator consider the following code

 

--Modified--

for ($i=1;$i<=15;$i++)
{
   if (($i%3) == 0)
  {
     echo $i;
  }

}

[BenInBlack]

??? In mathematics, a prime number (or a prime) is a natural number which has exactly two distinct natural number divisors: 1 and itself.

[rajivgonsalves]

hmm.. come to think about it, it is did not think about that when I provided the a solution  , just provided the requested code

[BenInBlack]

your code was fine  , I just wanted to point that out in case he had a misconception of what prime numbers are 

[phpQuestioner]

well the thing of it is; I am trying to check the to see if my "skip" variable is equal to 30, 60, or 90 with an array and an if condition. what is the best way for me to do this? i guess prime numbers wasn't what I meant.

[rajivgonsalves]

your if statement should be

 

if (($variable%30) != 0)
  {
     do something
  }

[phpQuestioner]

that doesn't quit do what I am trying to accomplish

 

here is what I have:

 

for ($i = 0; $i < $tp; $i++)
{
$display="15";
$pganteqty = $display * $i;
$ci = $i + 1;
if($ci<=3) {
$checker1 = $display * 3;
$checker2 = $display * 6;
if (($skip >= $checker1) && ($skip <= $checker2))
  {
   echo " <a href=\"$thispage?skip=". ($pganteqty + ($display * 3)) ."\">". ($ci + 3) ."</a> ";
  }
else
  {
   echo " <a href=\"$thispage?skip=$pganteqty\">$ci</a> ";
  }
}
}

 

now instead of using a lot of if else conditions to accomplish this; I want to figure out how to do this every time my "skip" variable is increases by 30 (30,60,90,120, and so on.........).