Cumulative sum in PHP Array from MySQL Query - php

Question

I want to do a cumulative sum of data from MySQL query. Already my SQL query working well but i don't know how to do a cumulative sum of column 'suma'. I want to stay with dates from MySQL query table but it should look like this that next index will have cumulative sum of this index and previous.
My array from MySQL query look like this.
[0] => Array
(
[data] => 2017-11-01
[SUMA] => 19
)
[1] => Array
(
[data] => 2017-11-02
[SUMA] => 97
)
[2] => Array
(
[data] => 2017-11-03
[SUMA] => 296
)
[3] => Array
(
[data] => 2017-11-05
[SUMA] => 58
)
[4] => Array
(
[data] => 2017-11-06
[SUMA] => 216
)
[5] => Array
(
[data] => 2017-11-07
[SUMA] => 194
)
[6] => Array
(
[data] => 2017-11-08
[SUMA] => 444
)
[7] => Array
(
[data] => 2017-11-09
[SUMA] => 301
)
[8] => Array
(
[data] => 2017-11-10
[SUMA] => 213
)
[9] => Array
(
[data] => 2017-11-11
[SUMA] => 5
)
[10] => Array
(
[data] => 2017-11-12
[SUMA] => 8
)
[11] => Array
(
[data] => 2017-11-13
[SUMA] => 186
)
[12] => Array
(
[data] => 2017-11-14
[SUMA] => 227
)
[13] => Array
(
[data] => 2017-11-15
[SUMA] => 180
)
[14] => Array
(
[data] => 2017-11-16
[SUMA] => 225
)
)
And I want to this array or new one look like this:
[0] => Array
(
[data] => 2017-11-01
[SUMA] => 19
)
[1] => Array
(
[data] => 2017-11-02
[SUMA] => 116
)
[2] => Array
(
[data] => 2017-11-03
[SUMA] => 412
)
[3] => Array
(
[data] => 2017-11-05
[SUMA] => 470
)
[4] => Array
(
[data] => 2017-11-06
[SUMA] => 686
)
[5] => Array
(
[data] => 2017-11-07
[SUMA] => 880
)
[6] => Array
(
[data] => 2017-11-08
[SUMA] => 1324
)
[7] => Array
(
[data] => 2017-11-09
[SUMA] => 1625
)
[8] => Array
(
[data] => 2017-11-10
[SUMA] => 1838
)
[9] => Array
(
[data] => 2017-11-11
[SUMA] => 1843
)
[10] => Array
(
[data] => 2017-11-12
[SUMA] => 1851
)
[11] => Array
(
[data] => 2017-11-13
[SUMA] => 2037
)
[12] => Array
(
[data] => 2017-11-14
[SUMA] => 2264
)
[13] => Array
(
[data] => 2017-11-15
[SUMA] => 2444
)
[14] => Array
(
[data] => 2017-11-16
[SUMA] => 2699
)
I tried like this but it's only showing me last date and full cumulative instead of each index.
while ($row = mysqli_fetch_assoc($result)) {
$myArray['data'] = $row['data'];
$myArray['suma'] += $row['SUMA'];
}

Answer 1

Do it while creating array
$s=0;
$myArray = [];
while ($row = mysqli_fetch_assoc($result)) {
$temp['data'] = $row['data'];
$s = $temp['suma'] = $row['SUMA'] + $s;
$myArray[] = $temp;
}
echo '<pre>';
print_r($myArray);

Answer 2

<?php
$array=array(
0 => Array
(
'data' => '2017-11-01',
'SUMA' => 19
),
1 => Array
(
'data' => '2017-11-02',
'SUMA' => 97
),
2 => Array
(
'data' => '2017-11-03',
'SUMA' => 296,
),
3 => Array
(
'data' => '2017-11-05',
'SUMA' => 58,
),
);
$i=0;
while ($i<count($array) )
{
if($i==0) {
$newArray[0]['data'] = $array[$i]['data'];
$newArray[0]['SUMA'] = $array[$i]['SUMA'];
}
else{
$newArray[$i]['data']=$array[$i]['data'];
$newArray[$i]['SUMA']=$array[$i]['SUMA']+$newArray[$i-1]['SUMA'];
}
$i++;
}
echo '<pre>';
print_r($newArray);
and the output is :
Array
(
[0] => Array
(
[data] => 2017-11-01
[SUMA] => 19
)
[1] => Array
(
[data] => 2017-11-02
[SUMA] => 116
)
[2] => Array
(
[data] => 2017-11-03
[SUMA] => 412
)
[3] => Array
(
[data] => 2017-11-05
[SUMA] => 470
)
)
You can remove the if/else and keep only the else but you get a notice for position -1 of the array. The code is working fine you just have to disable the notice warning (i don't recommend it do it only if you are 100% sure)