问题
I have seen various posted about this question so am aware some answers to this may exist. however I am none the wiser after reading these.
I have an array that is like the following.
[0] => Array
(
[id] => 95659865986
[invoiceNumber] => 6374324
[invoiceTitle] => Monthly
[invoiceStatus] => Paid
[accountId] => 6235218753
[totalExVat] => 158.95
[dateCreated] => 1 Apr 2012
[vatAmount] => 20.00
)
All I wish to do is do array sum on the vatAmount values of this array.
As the following doesnt seem to be doing much.
(array_sum($account_invoices[\'vatAmount\'])
回答1:
Just a way to do it:
$sum = 0;
foreach($account_invoices as $num => $values) {
$sum += $values[ 'vatAmount' ];
}
回答2:
If you have PHP 5.5+ you can do this without looping or using a callback (since function calls are relatively expensive) ... just use:
$sum = array_sum(array_column($account_invoices, 'vatAmount'));
回答3:
I would use array_map to reduce the array to only what is needed. Bear in mind, this will only work with PHP 5.3 onwards.
$total_vat = array_sum( array_map(
function($element){
return $element['vatAmount'];
},
$account_invoices));
回答4:
You could use array_map first to collect the vatAmout value.
$sum = array_sum(array_map(function($var) {
return $var['vatAmout'];
}, $account_invoices));
回答5:
A way to do this using a PHP 5.3+ anonymous function
$account_invoices = array(
0 => array(
'id' => '95659865986',
'invoiceNumber' => '6374324',
'invoiceTitle' => 'Monthly',
'invoiceStatus' => 'Paid',
'accountId' => '6235218753',
'totalExVat' => 158.95,
'dateCreated' => '1 Apr 2012',
'vatAmount' => 20.00
),
1 => array(
'id' => '95659865987',
'invoiceNumber' => '6374325',
'invoiceTitle' => 'Monthly',
'invoiceStatus' => 'Paid',
'accountId' => '6235218753',
'totalExVat' => 208.95,
'dateCreated' => '1 May 2012',
'vatAmount' => 25.00
),
);
$sumDetail = 'vatAmount';
$totalVAT = array_reduce($account_invoices,
function($runningTotal, $record) use($sumDetail) {
$runningTotal += $record[$sumDetail];
return $runningTotal;
},
0
);
echo $totalVAT;
回答6:
You can do this using array_map() and select the vatAmount column first:
$totalVatAmount = array_sum(array_map(function($account_invoices) {
return $account_invoices['vatAmount'];
}, $account_invoices));
Of course, internally this performs a double loop; it's just that you don't see it inside the code. If you use array_reduce() then you can get rid of one loop:
$totalVatAmount = array_reduce($account_invoices,
function($totalAmount, $item) {
$totalAmount += $item['vatAmount'];
return $totalAmount;
},
0
);
However, if speed is the only interest, you should use foreach. Because there is no function calls used to calculate the final sum. This solution is faster than other solution.
$totalVatAmount = 0;
foreach ($account_invoices as $item) {
$totalVatAmount += $item['vatAmount'];
}
回答7:
You can't do this directly with array_sum, which would sum everything in the array.
You can do it with a loop:
$sum = 0;
foreach($items as $item)
$sum += $item['vatAmount'];
or you can filter the array (in this case it isn't very convenient, but if you had to calculate, say, S&H expenses plus VAT plus..., from each single item, and then sum...):
// Input: an array (element #n of array of arrays), output: VAT field
function getVAT($item)
{
return $item['vatAmount'];
}
// Array with all VATs
$vats = array_map('getVAT', $items);
$sum = array_sum($vats);
回答8:
Also you can do this (if you like array_sum function):
foreach($account_invoices as $num => $values) {
$vatAmount[] = $values[ 'vatAmount' ];
}
$Total = array_sum($vatAmount);
回答9:
Just another way to do this using array_reduce:
$vatMount = array_reduce($account_invoices, function($total, $value) {
return $total + $value['vatAmount'];
});
来源:https://stackoverflow.com/questions/12838729/multidimensional-array-array-sum