Question

我正在尝试将高级别的产品评论数据插入到SKU记录中，但我仍然试图获得重复密钥的平均值。

Array
(
    [0] => Array
        (
            [sku] => 70835
            [rating] => 5
        )

    [1] => Array
        (
            [sku] => F6W/35
            [rating] => 5
        )

    [2] => Array
        (
            [sku] => 36865
            [rating] => 5
        )

    [3] => Array
        (
            [sku] => 36835
            [rating] => 5
        )

    [4] => Array
        (
            [sku] => F30W/T8/830/POLYLUX
            [rating] => 2
        )

    [5] => Array
        (
            [sku] => 70835
            [rating] => 4
        )
)

我想获得重复skus的平均评分，因此预期输出为：

Array
(
    [0] => Array
        (
            [sku] => 70835
            [rating] => 4.5
        )

    [1] => Array
        (
            [sku] => F6W/35
            [rating] => 5
        )

    [2] => Array
        (
            [sku] => 36865
            [rating] => 5
        )

    [3] => Array
        (
            [sku] => 36835
            [rating] => 5
        )

    ...
)

我有以下循环，它是对重复项进行求和，但我很难获得平均值

foreach ($reviews as $val) {
    if (!isset($result[$val['sku']]))
    {
        $result[$val['sku']] = $val;
    }
    else{
        $result[$val['sku']]['rating'] += $val['rating'];
        #This will sum the duplicated ratings but I need to divide the sum here by the number of times the 'sku' index was duplicated so in the example 9/2 = 4.5
    }
}

提前感谢！

Answer 1

这应该适合你：

foreach ($reviews as $val) {
    if (!isset($result[$val['sku']]))
    {
        $result[$val['sku']] = array('rating' => $val['rating'], 'count' => 1);
    }
    else{
        $result[$val['sku']]['rating'] += $val['rating'];
        $result[$val['sku']]['count']++;
    }
}

foreach ($result as &$val) {
    $val['average'] = $val['rating'] / $val['count'];
}

请注意，如果此数据来自数据库，则使用GROUP BY语句可以更轻松地执行此操作。

Answer 2

[akshay@localhost tmp]$ cat test.php
<?php

$array = array (
  0 => 
  array (
    'sku' => '70835',
    'rating' => '5',
  ),
  1 => 
  array (
    'sku' => 'F6W/35',
    'rating' => '5',
  ),
  2 => 
  array (
    'sku' => '36865',
    'rating' => '5',
  ),
  3 => 
  array (
    'sku' => '36835',
    'rating' => '5',
  ),
  4 => 
  array (
    'sku' => 'F30W/T8/830/POLYLUX',
    'rating' => '2',
  ),
  5 => 
  array (
    'sku' => '70835',
    'rating' => '4',
  ),
);

$final=$count=array();

foreach($array as $v)
{
    if(isset($final[$v['sku']]))
    {
      $final[$v['sku']]['rating'] += $v['rating'];
      $count[$v['sku']]++;
    }else
    {
      $final[$v['sku']] = $v;
      $count[$v['sku']] = 1;
    }

}

array_map( function($a, $b) use (&$final){ $final[$a]['rating']/=$b; }, array_keys($count),array_values($count));
unset($count);

// Input
print_r($array);

// Output
print_r( array_values($final));

?>

<强> 输出

[akshay@localhost tmp]$ php test.php
Array
(
    [0] => Array
        (
            [sku] => 70835
            [rating] => 5
        )

    [1] => Array
        (
            [sku] => F6W/35
            [rating] => 5
        )

    [2] => Array
        (
            [sku] => 36865
            [rating] => 5
        )

    [3] => Array
        (
            [sku] => 36835
            [rating] => 5
        )

    [4] => Array
        (
            [sku] => F30W/T8/830/POLYLUX
            [rating] => 2
        )

    [5] => Array
        (
            [sku] => 70835
            [rating] => 4
        )

)
Array
(
    [0] => Array
        (
            [sku] => 70835
            [rating] => 4.5
        )

    [1] => Array
        (
            [sku] => F6W/35
            [rating] => 5
        )

    [2] => Array
        (
            [sku] => 36865
            [rating] => 5
        )

    [3] => Array
        (
            [sku] => 36835
            [rating] => 5
        )

    [4] => Array
        (
            [sku] => F30W/T8/830/POLYLUX
            [rating] => 2
        )

)

Answer 3

如何为结果数组添加计数字段...

foreach ($reviews as $val) {
    if (!isset($result[$val['sku']]))
    {
        $result[$val['sku']] = $val;
        $result[$val['sku']]["count"] = 1;
    }
    else{
        $result[$val['sku']]['rating'] += $val['rating'];
        $result[$val['sku']]["count"] ++;
    }
}

foreach($result as $k => $v) {
    $result[$k]['avg'] = $v['rating']/$v['count'];
}

PHP多维数组，重复值的平均值

3 个答案: