如何求多维关联数组的和？

Question

如何对多维关联数组的值求和？

我的数组如下：

$testarray=[];

$testarray[]=[

    "2019-12-31" => [

        "category1" => [

            "total" => "10"

            ],

        "category2" => [

            "total" => "20"

            ],

        ],

    "2020-01-31" => [

        "category1" => [

            "total" => "100"

            ],

        "category2" => [

            "total" => "200"

            ],

        ],

    "2020-02-28" => [

        "category1" =>  [

            "total" => "1000"

            ],

        "category2" => [

            "total" => "2000"

            ]

        ],

    ];

我尝试了以下方法：

foreach($testarray[0] as $Offset=>$ArrayOfResults){

    foreach($ArrayOfResults as $ResultOffset=>$Result){

        $total+= $Result["total"];

    }

    $sums[$Offset]=$total;

}

结果是：

"2019-12-31" => 30

"2020-01-31" => 330

"2020-02-28" => 3330

如何获得所需的结果，如下将类别 1 和类别 2 值相加：

"2019-12-31" => 30

"2020-01-31" => 300

"2020-02-28" => 3000

Answer 1

array_sum()使用and代替嵌套循环array_column()。foreach ($testarray[0] as $date => $results) {     $sums[$date] = array_sum(array_column($results, 'total'));

Answer 2

您只需要重置$total每次迭代：foreach($testarray[0] as $Offset=>$ArrayOfResults){     $total = 0;    foreach($ArrayOfResults as $ResultOffset=>$Result){        $total+= $Result["total"];    }    $sums[$Offset]=$total;}