Php 获取MongoDB中多个嵌入文档的平均数量

我正在使用highcharts制作一个向下展开的图表。这将显示多个具有平均值的项目，并将在具有每个值的列中向下展开。问题是，我无法得到每个项目的平均数量。。 来自mongo的JSON如下所示：

{
    "_id" : ObjectId("57f4dd6c45db428df9a5541b"),
    "id" : 68,
    "project_code" : 13110202,
    "samples" : [
                {
                        "sample_name" : "1678_2",
                        "perc" : "75.97"
                },
                {
                        "sample_name" : "2012_1B-5",
                        "perc" : "75.33",
                },
                {
                        "sample_name" : "2012_1B-8",
                        "perc" : "77.28",                 
                }]
},    {
    "_id" : ObjectId("57f4dd6c45db428df9a5541a"),
    "id" : 70,
    "project_code" : 1235125,
    "samples" : [
                {
                        "sample_name" : "Ben",
                        "perc" : "30.97"
                },
                {
                        "sample_name" : "Anna",
                        "perc" : "81.25",
                },
                {
                        "sample_name" : "Sarah",
                        "perc" : "80.23",                 
                }]
},

我试图浏览文档，通过嵌入的文档示例，获取所有perc_映射值，计算平均值，并将其放入用于HighChart的JSON中。我现在拥有的代码：

foreach ($id_array as $char) {
            $cursor = $collection->find(array("_id" => new MongoId($char)));
            foreach ($cursor as $document) {
                if (is_array($document['samples'])) {
                    foreach ($document['samples'] as $samples) {
                        array_push($perc_total, $samples['perc']);
                        $average_of_foo = array_sum($perc_total) / count($perc_total);
                    }
                }
            }
        }

        var_dump($average_of_foo);   


        foreach ($id_array as $char) {
            $cursor = $collection->find(array("_id" => new MongoId($char)));
            foreach ($cursor as $document) {
                if (is_array($document['samples'])) {
                    foreach ($document['samples'] as $samples) {
                        $array =
                            array("name" => $document['project_code'],
                              // Here is will add the average
                                "y" => (float) $samples['perc'],
                                "drilldown" => $char
                            );
                        array_push($array_data, $array);
                    }
                }
            }
        }

---

能否请您的问题包含所需的JSON输出？此外，您可能需要更改模式设计，即将

perc_映射的

值转换为数字值，而不是当前的字符串。那么，您当前代码的哪一部分不工作？我已经让它工作了！我将很快用解决方案更新我的问题。