PHP: Calculate average value based on fixed values

Question

Out of a variable number of values I need to calculate the average. The challenge: The average can only be one of the following fixed values (the closest!):

$allowedAverageValues = [0.66, 1, 1.33, 1.66, 2]

I calculate the average as follows:

$randomValues = [1.33, 1, 0.66, 1, 2, 1.33];
$average = array_sum($randomValues)/count($randomValues); // returns 1.22

How can I identify the value in $allowedAverageValues that is closest to $average? So the desired result is 1.33.

Possible duplicate of https://stackoverflow.com/questions/5464919/find-a-matching-or-closest-value-in-an-array — misorude, Dec 12 '18 at 13:21
(Duplicate easily found by googling “php find closest numeric value” - that the value is an average in this particular case, doesn’t change the solution one bit, and therefor neither what you should have researched to begin with …) — misorude, Dec 12 '18 at 13:23
Possible duplicate of [Find a matching or closest value in an array](https://stackoverflow.com/questions/5464919/find-a-matching-or-closest-value-in-an-array) — DEarTh, Dec 12 '18 at 13:31

executable · Accepted Answer · 2018-12-12T13:34:25.413

0

I think this is what you're looking for :

<?php
function getClosest($search, $arr) {
   $closest = null;
   foreach ($arr as $item) {
      if ($closest === null || abs($search - $closest) > abs($item - $search)) {
         $closest = $item;
      }
   }
   return $closest;
}

$randomValues = [1.33, 1, 0.66, 1, 2, 1.33];
$average = array_sum($randomValues)/count($randomValues); // returns 1.22
$res = getClosest($average, $randomValues);

print_r($res); // returns 1.33

Function from the first answer Find a matching or closest value in an array

edited Dec 12 '18 at 13:34

answered Dec 12 '18 at 13:19

executable

3,365
6
24
52

3

You shouldn't copy an answer from another question. If a question is a duplicate you can mark it. – Maksym Fedorov Dec 12 '18 at 13:35

score 0 · Answer 2 · answered Dec 12 '18 at 13:38

$arr = [0.66, 1, 1.33, 1.66, 2];

function getNearest($arr,$var){
    usort($arr, function($a,$b) use ($var){

        return  abs($a - $var) - abs($b - $var);
    });
   return array_shift($arr);
}

$randomV = [1.33, 1, 0.66, 1, 2, 1.33];
$ave = array_sum($randomV)/count($randomV); 
$res = getNearest($ave, $randomV);

print_r($res);

PHP: Calculate average value based on fixed values

2 Answers2