Php 我想将重复的tag_name数组分组到一个数组下

从以下数组：

Array
(
    [0] => Array
        (
            [tag_name] => Quant-Arithmetic
            [student_marks] => 1.05
            [total_marks] => 2.00
            [student_count] => 1
            [level] => Easy
            [overall_percentage] => 52
        )

    [1] => Array
        (
            [tag_name] => Quant-Arithmetic
            [student_marks] => 1.10
            [total_marks] => 4.00
            [student_count] => 1
            [level] => Medium
            [overall_percentage] => 28
        )

    [2] => Array
        (
            [tag_name] => Quant-Algebra
            [student_marks] => 0.20
            [total_marks] => 1.00
            [student_count] => 1
            [level] => Easy
            [overall_percentage] => 20
        )

    [3] => Array
        (
            [tag_name] => Quant-Algebra
            [student_marks] => 1.00
            [total_marks] => 6.00
            [student_count] => 1
            [level] => Medium
            [overall_percentage] => 17
        )

    [4] => Array
        (
            [tag_name] => Quant-Algebra
            [student_marks] => 1.50
            [total_marks] => 6.00
            [student_count] => 1
            [level] => Hard
            [overall_percentage] => 25
        )

)

类似的事情：因为我需要一个基于标记名的数组，它的所有级别都在该数组中，这样我就可以得到单个标记名及其级别和百分比，以便进一步计算

[tag_name]
{
 [level]:[overall_percentage]
 [level]:[overall_percentage]
 .
 .
}
.
.
.

这将添加并创建一个$newArray，如下所示：

 Array(
    'tag_name' => Array(
        'Medium' => '27'
     )
 )

试试这个代码

$array =array
(
  '0' => array
    (
        'tag_name' => 'Quant-Arithmetic',
        'student_marks' => ' 1.05',
        'total_marks' => ' 2.00',
        'student_count' => ' 1',
        'level' => ' Easy',
        'overall_percentage' => ' 52',
    ),

'1' => array
    (
        'tag_name' => ' Quant-Arithmetic',
        'student_marks' => ' 1.10',
        'total_marks' => ' 4.00',
        'student_count' => ' 1',
        'level' => ' Medium',
        'overall_percentage' => ' 28',
    ),

'2' => array
    (
        'tag_name' => ' Quant-Algebra',
        'student_marks' => ' 0.20',
        'total_marks' => ' 1.00',
        'student_count' => ' 1',
        'level' => ' Easy',
        'overall_percentage' => ' 20',
    )
    );
    // declare a new array
$new_array = array();
foreach($array as $values){
  // trim array elements
  $trimmed_array=array_map('trim',$values);
  if(isset($new_array[$trimmed_array['tag_name']])){
    //add elements to array
    $new_array[$trimmed_array['tag_name']][$trimmed_array['level']] = $trimmed_array['overall_percentage'];
}else{
    // create new array
    $new_array[$trimmed_array['tag_name']] = array($trimmed_array['level'] => $trimmed_array['overall_percentage']);
  }
}

// php array
print_r($new_array);
// json
echo json_encode($new_array);

输出：数组

Array
(
[Quant-Arithmetic] => Array
    (
        [Easy] => 52
        [Medium] => 28
    )

[Quant-Algebra] => Array
    (
        [Easy] => 20
    )

)

输出：Json

{"Quant-Arithmetic":{"Easy":"52","Medium":"28"},"Quant-Algebra":{"Easy":"20"}}

---

你试过什么吗？你想要什么？JSON还是数组？JSON和数组都在这里：你确定这是OP想要的吗？我认为你的循环是完美的，但不是输出。我已经编辑了我的响应。我的原始版本包含了一个额外的数组级别深度，因为我觉得会有多个级别具有相同的键值（例如2x Easy）

{"Quant-Arithmetic":{"Easy":"52","Medium":"28"},"Quant-Algebra":{"Easy":"20"}}