How to optimise the array calcuation using loops? - php

Question

Hey i have array calculation where i need to refactor this code using loops please suggest...
<?php
arr = [286538,237034,192724,150815,117523,82754,49707];
$a1 = $arr[0]/7;
$a2 = ($a1+$arr[1])/7;
$a3 = ($a1+$a2+$arr[2])/7;
$a4 = ($a1+$a2+$a3+$arr[3])/7;
$a5 = ($a1+$a2+$a3+$a4+$arr[4])/7;
$a6 = ($a1+$a2+$a3+$a4+$a5+$arr[5])/7;
$a7 = ($a1+$a2+$a3+$a4+$a5+$a6+$arr[6])/7;
?>
Output -
40934
39709.714285714
39052.530612245
38644.463556851
39409.10120783
40071.972808949
41075.540353084

Answer 1

Here is how you can utilize loops in your problem:
$arr = [286538,237034,192724,150815,117523,82754,49707];
$newArr = [];
$counter = 0;
while($counter < count($arr)){
$sum = array_sum($newArr);
$newArr[] = ($sum + $arr[$counter]) / 7;
$counter++;
}

Answer 2

<?php
$arr = [286538,237034,192724,150815,117523,82754,49707];
function calcarr($n){
$result = 0;
global $arr;
if ($n <= 0) return $result;
for ($i=0;$i<$n;$i++) $result += calcarr($i);
return ($result + $arr[$n-1])/7;
}
$a1 = $arr[0]/7;
$a2 = ($a1+$arr[1])/7;
$a3 = ($a1+$a2+$arr[2])/7;
$a4 = ($a1+$a2+$a3+$arr[3])/7;
$a5 = ($a1+$a2+$a3+$a4+$arr[4])/7;
$a6 = ($a1+$a2+$a3+$a4+$a5+$arr[5])/7;
$a7 = ($a1+$a2+$a3+$a4+$a5+$a6+$arr[6])/7;
echo "$a7\n";
echo calcarr(7)."\n";
?>
RESULT:
41075.540353084
41075.540353084

Answer 3

<?php
$arr = [286538,237034,192724,150815,117523,82754,49707];
$result = [];
foreach($arr as $k => $item)
$result["a$k"] = (float) (array_sum($result) + $item)/7;
var_dump($result);
Output:
array(7) {
["a0"]=>
float(40934)
["a1"]=>
float(39709.714285714)
["a2"]=>
float(39052.530612245)
["a3"]=>
float(38644.463556851)
["a4"]=>
float(39409.10120783)
["a5"]=>
float(40071.972808949)
["a6"]=>
float(41075.540353084)
}
If you want the variables as you have listed:
extract($result);
If you don't care about keys and to extract those variables, this will just give you a 0 indexed array as for your result:
foreach($arr as $item)
$result[] = (float) (array_sum($result) + $item)/7;