php中数组结构的改变

我对编程一无所知，我的任务是改变数组的结构，但我就是不能让它工作

这是原始阵列：

[0] => Array
    (
        [att_values_id] => 5
        [att_value] => Sloping
        [att_id] => 5
        [att_category] => Frame
    )

[1] => Array
    (
        [att_values_id] => 13
        [att_value] => Time Trial
        [att_id] => 5
        [att_category] => Frame
    )

[2] => Array
    (
        [att_values_id] => 21
        [att_value] => Mountain
        [att_id] => 5
        [att_category] => Frame
    )

[3] => Array
    (
        [att_values_id] => 15
        [att_value] => Carbon
        [att_id] => 3
        [att_category] => Material
    )

[4] => Array
    (
        [att_values_id] => 15
        [att_value] => Titanium
        [att_id] => 9
        [att_category] => Frame
    )

[5] => Array
    (
        [att_values_id] => 15
        [att_value] => Aluminum
        [att_id] => 17
        [att_category] => Frame
    )

[6] => Array
    (
        [att_values_id] => 7
        [att_value] => Expensive
        [att_id] => 12
        [att_category] => Price
    )

[7] => Array
    (
        [att_values_id] => 7
        [att_value] => Moderate
        [att_id] => 33
        [att_category] => Price
    )

[8] => Array
    (
        [att_values_id] => 7
        [att_value] => Entry Level
        [att_id] => 40
        [att_category] => Price
    )

我必须把它改成这样：

Array
   (
       [Frame] => Array
           (
                [5] => Sloping
                [13] => Mountain
                [21] => Time Trial
            )
       [Material] => Array
           (
                [3] => Carbon
                [9] => Titanium
                [17] => Aluminum
            )
       [Price] => Array
           (
                [12] => Expensive
                [33] => Moderate
                [40] => Entry Level
            )
      )

---

我已经尝试使用foreach来遍历数组，但我不知道如何构建新数组。

在明确完成作业之前，这个小伪代码是最接近的

foreach (firstarray as key => value) {
 newarray[value['att_category']][value['att_id']]=value['att_value'];
}

---

一点也不，我现在的工作岗位是负责在我们的网站上实现新功能，因为我说过我对编程很陌生，而且年纪太大了，不适合上学。谢谢你，阿梅纳迪尔，尽管我不是学生。