Get sum of objects with same id inside nested array php - php

Question

This is my array of objects in php:
Array( [0]=>
Array (
[added_time] => 2018-12-09 14:00:00+00
[id] => 123
[places] =>
[{
"place_id" : 1,
"total" : 5,
"empty" : 0,
"weight" : 68000,
"persons" :
[{
"person_id" : 2,
"person_name" : "ABC",
"total":100
},
{
"person_id" : 3
"person_name" : "DEF",
"total":200
}]
},
"place_id" : 4,
"total" : 10,
"empty" : 0,
"weight" : 54000,
"persons" :
[{
"person_id" : 2,
"person_name" : "ABC"
"total":100
},
{
"person_id" : 6
"person_name" : "GHI",
}
]
],
),
Array (
[added_time] => 2018-12-09 15:00:00+00
[id] => 456
[places] =>
[{
"place_id" : 1,
"total" : 5,
"empty" : 0,
"weight" : 68000,
"persons" :
[{
"person_id" : 2,
"person_name" : "ABC",
"total":200
},
{
"person_id" : 3
"person_name" : "DEF",
"total":300
}]
}]
)
)
I am trying to get sum on the base of person_id like group by person_id.
My desired result should be:
Array (
[added_time] => 2018-12-09 14:00:00+00
[id] => 123
persons:array(
Array([0]=>
[person_id] : 2,
[person_name] : "ABC",
[total]:200
),
Array([1]=>
[person_id] : 3,
[person_name] : "DEF",
[total]:300
),
Array([2]=>
[person_id] : 6,
[person_name] : "GHI",
[total]:500
)
),
[added_time] => 2018-12-09 15:00:00+00
[id] => 123
persons:array(
Array([0]=>
[person_id] : 2,
[person_name] : "ABC",
[total]:200
),
Array([1]=>
[person_id] : 3,
[person_name] : "DEF",
[total]:300
)
)
)
How can I achieve this result. I can use foreach but I don't want to use it because of three iterations.
Is there any other method to achieve this in php and without any performance issue?

Answer 1

You can have that by using PHP function as array-merge, array-column, array-reduce.
Let divided that to 3 step:
1.Sum total for all person given list of persons. Define the the following reduce function:
function reduce($carry, $item)
{
if (!in_array($item["person_name"], array_column($carry, "person_name")))
$carry[] = $item;
else {
foreach($carry as &$person) {
if ($item["person_name"] == $person["person_name"])
$person["total"] += $item["total"];
}
}
return $carry;
}
2.For every element in your array create you output using the reduce from step 1:
function reduceElement($arr) {
$res = array("added_time" => $arr["time"], "id" => $arr["id"]);
$persons = array();
foreach($arr["places"] as $place) {
$persons = array_merge($persons, $place["persons"]);
}
$res["persons"] = array_reduce($persons, "reduce", array());
return $res;
}
3.Combine it all:
$elemA= array("id"=>1, "time"=>"2018", "places" => array(array("persons" => array(array("person_name" => "ABC", "total" => 100), array("person_name" => "DEF", "total" => 200))), array("persons" => array(array("person_name" => "ABC", "total" => 100), array("person_name" => "GHI", "total" => 100)))));
$elemB = array("id"=>2, "time"=>"2017", "places" => array(array("persons" => array(array("person_name" => "ABC", "total" => 200), array("person_name" => "DEF", "total" => 300)))));
$arr = array($elemA, $elemB);
$res = array();
foreach($arr as $obj)
$res[] = reduceElement($obj);
print_r($res);
This will give you the require out put