Question

给出以下JSON：

[
    {
        "group": "satellite-1",
        "data": [
            {
                "label": "feed1-1_TargetA",
                "data": [
                    {"timeRange": ["11:40:00 AM", "11:40:20 AM"], val: "TargetA"},
                    {"timeRange": ["11:40:20 AM", "11:40:40 AM"], val: "TargetA"},
                    {"timeRange": ["11:41:00 AM", "11:41:20 AM"], val: "TargetA"},
                ]
            },
            {
                "label": "feed1-1_TargetB",
                "data": [
                    {"timeRange": ["11:40:40 AM", "11:41:00 AM"], val: "TargetB"},
                    {"timeRange": ["11:41:00 AM", "11:41:20 AM"], val: "TargetB"}
                ]
            },
            {
                "label": "feed1-1_TargetC",
                "data": [
                    {"timeRange": ["11:40:40 AM", "11:41:00 AM"], val: "TargetC"},
                    {"timeRange": ["11:41:00 AM", "11:41:20 AM"], val: "TargetC"},
                ]
            },
            {
                "label": "feed1-1_TargetD",
                "data": [
                    {"timeRange": ["11:40:40 AM", "11:41:00 AM"], val: "TargetD"},
                    {"timeRange": ["11:41:00 AM", "11:41:20 AM"], val: "TargetD"},
                ]
            },
            {
                "label": "feed1-2_TargetB",
                "data": [
                    {"timeRange": ["11:40:20 AM", "11:40:40 AM"], val: "TargetB"}
                ]
            }

        ]
    },
    {
        "group": "satellite-2",
        "data": [
            {
                "label": "feed2-1_TargetA",
                "data": [
                    {"timeRange": ["11:40:20 AM", "11:40:40 AM"], val: "TargetA"},
                    {"timeRange": ["11:41:00 AM", "11:41:20 AM"], val: "TargetA"},
                ]
            },
            {
                "label": "feed2-1_TargetB",
                "data": [
                    {"timeRange": ["11:40:40 AM", "11:41:00 AM"], val: "TargetB"},
                    {"timeRange": ["11:41:00 AM", "11:41:20 AM"], val: "TargetB"}
                ]
            },
            {
                "label": "feed2-1_TargetC",
                "data": [
                    {"timeRange": ["11:40:40 AM", "11:41:00 AM"], val: "TargetC"},
                    {"timeRange": ["11:41:00 AM", "11:41:20 AM"], val: "TargetC"},
                ]
            },
            {
                "label": "feed2-2_TargetB",
                "data": [
                    {"timeRange": ["11:40:20 AM", "11:40:40 AM"], val: "TargetB"}
                ]
            }

        ]
    }
]

我试图比较哪些Feed看到了最多的目标。

到目前为止，我已经解决了这个问题，因为我可以循环访问JSON并通过比较每个Feed的长度来返回“最敏锐的Feed”。

/*
 * Compare length of each sensor block in data to determine which sensor
 * is most observant
 */
var getMostObservantFeeds = function(entry){
    var bestFeed = null;


    for(var d of entry.data){
        if (bestFeed == null){
            bestFeed = d;
        }
        if (bestFeed.data.length < d.data.length){
            bestFeed = d;
        }
    }

    bestFeed = bestFeed || {};

    return bestFeed.label
    ])
};

var getMostObservantFeed = function(data_JSON){
    return data_JSON.map(x => getMostObservantFeeds(x));
};

然而，对于饲料与另一种饲料长度相同的情况，我无法做到这一点。

如果2个Feed看到相同数量的目标（并且是看到的最高数量），我该如何返回最佳Feed的列表？（即satellite2：feed2-1_TargetA，feed2-1_TargetB，feed2-1_TargetC）

Answer 1

如何记录最大值并与每次比较。也许只是将标签存储在一个数组中，因为这就是你要回来的所有内容吗？

var getMostObservantFeed = function(entry){
    var bestLabels = [];
    var max = 0;

    for(var d of entry.data){
        if (d.data.length >= max){
            max = d.data.length;
            bestLabels.push(d.label);
        }
    }

    return bestLabels;
};

Answer 2

我建议您使用第二个条件来检查bestFeed.data和d.data是否具有相同的长度。在for循环中的第二个if语句之后添加类似的东西：

else if(bestFeed.data.length === d.data.length){  
    //do further checking here
}

在这种情况下，您可以再次比较bestfeed和d（可能是timerange属性）。

我还建议您使用d以外的其他内容，例如i或item

比较来自JSON的信息，返回列表中的顶部结果

2 个答案: