Sum for values in my array - php

Question

I have an array like below, and I want to do the total of values in a spefic manner where all values of val1_(.*) {regular expressions}, and similarly other values.
I have only specific vals like val1, val2, and val3.
My array is like:
$stats = Array
(
[ADDED_NEW_2012_06_12] => 16
[ADDED_OLD_2012_06_12] => 10
[ADD_LATER_2012_06_12] => 12
[ADDED_NEW_2012_06_11] => 16
[ADDED_OLD_2012_06_11] => 10
[ADD_LATER_2012_06_11] => 12
)
Can you please tell me how can i obtain my result. I don't know how to add such values using regex in php. Please help.

Answer 1

You don't necessarily need a regular expression if you can identify the values by the first part of the key.
Iterate over the array and create a new array with one element for each valX:
$totals = array();
// iterate over the array
foreach($array as $key => $value) {
$k = substr($key, 0, strpos($key, '_')); // get the first part (i.e. `valX`)
if(!isset($totals[$k])) { // if $totals['valX'] does not exist, initialize
$totals[$k] = 0;
}
$totals[$k] += $value; // sum
}
Reference: foreach, substr, strpos, isset

Answer 2

Do you mean this?
$array = array (
'val1_2012_06_12' => 16,
'val2_2012_06_12' => 10,
'val3_2012_06_12' => 12,
'val1_2012_06_11' => 16,
'val2_2012_06_11' => 10,
'val3_2012_06_11' => 12,
);
$sums = array();
foreach ($array as $key => $value) {
$regex = '~(?P<prefix>val\d+)_\d{4}_\d{2}_\d{2}~';
if (preg_match($regex, $key, $matches)) {
$sums[$matches['prefix']] += $value;
}
}
It will produce something like this, it will group sums by prefixes:
Array
(
[val1] => 32
[val2] => 20
[val3] => 24
)

Answer 3

Edit: updated to the refined question
You can match the key against a code, and create a sum from there like this with a simple foreach loop.
$array = array(
'ADDED_NEW_2012_06_12' => 16,
'ADDED_OLD_2012_06_12' => 10,
'ADD_LATER_2012_06_12' => 12,
'ADDED_NEW_2012_06_11' => 16,
'ADDED_OLD_2012_06_11' => 10,
'ADD_LATER_2012_06_11' => 12,
);
$sumarray = array();
foreach ($array as $key => $value)
{
$matches = array();
preg_match("/^(\w+?_\w+?)_/i", $key, $matches);
$key = $matches[1];
if (!isset($sumarray[$key]))
{
$sumarray[$key] = $value;
} else {
$sumarray[$key] = $sumarray[$key] + $value;
}
}
print_r($sumarray);

Answer 4

if you have just this tree type of value in array so you can use this:
$stats = Array(
'ADDED_NEW_2012_06_12' => 16,
'ADDED_OLD_2012_06_12' => 10,
'ADD_LATER_2012_06_12' => 12,
'ADDED_NEW_2012_06_11' => 16,
'ADDED_OLD_2012_06_11' => 10,
'ADD_LATER_2012_06_11' => 12
);
foreach($stats as $key => $value)
{
$substring=substr($key, 0 , 9);
if($substring=='ADDED_NEW')
#$ADDED_NEW += $value;
elseif($substring=='ADDED_OLD')
#$ADDED_OLD += $value;
else
#$ADD_LATER += $value;
}
echo 'ADDED_NEW : ' . $ADDED_NEW .'<br>ADDED_OLD : ' . $ADDED_OLD .'<br>ADD_LATER : ' . $ADD_LATER ;
Output :
ADDED_NEW : 32
ADDED_OLD : 20
ADD_LATER : 24

Answer 5

$sum = 0;
Foreach($object as $key=>$value){
$sum += $value;
}