title: Efficient way to work with large array
body: <p>I have a large-ish array of around 500 integer values. I have another integer, which I need to test against each of the values in the array to see if it meets the condition of being between the array value - 15 and the array value + 15. Other than just iterating through each value in the array and doing the comparison, is there a neater, more efficient way to do this? I'm using PHP 5.2 </p>
  
  <p>EDIT: So if i have array(10,...,2500) and $n = 2510, I want to see if $n matches the condition of being between 15 either side of any of the array values. In this case, the condition would be true for the last value, 2500. </p>
  
  <p>I realise 500 isn't exactly a monstrous array :)</p>