In this post, this function will round the number to half a unit in php.

1. Code:

  <?php 
   function roundHalfUp($number){
		$n = (int)$number;
		$frac = $number - $n;
		if ($frac > 0 && $frac < 0.5) {
			$number = $n + 0.5;
		} else if ($frac > 0.5) {
			$number = $n + 1;
		}
		return $number;
	}
    $number = 8.1;
    echo roundHalfUp($number);
	$number = 8.6;
    echo roundHalfUp($number);
    ?> 

2. Example:

Input:

Number input: 8.1
Number input: 8.6

Output:

Output: 8.5
Output: 9