Question

这是一个简单的JSON数据集

var data =  [
            {name: "Alex", type: "human", legs: 2},
            {name: "Lassie", type: "dog", legs: 4},
            {name: "Spot", type: "dog", legs: 4},
            {name: "Polly", type: "bird", legs: 2},
            {name: "Fiona", type: "plants", legs: 0},
            ]

我可以根据类型创建一个crossfilter：

typeDimension.filter("dog");

对此的否定怎么样？？

typeDimension.filter(not("dog"));

这是否可以使用crossfilter ......？

Answer 1

是的，你可以这样做。一种方法是使用filterFunction method on your dimension，并提供一个函数来检查给定的数据是否不等于dog。这是一个完整的例子：

var data =  crossfilter([
            {name: "Alex", type: "human", legs: 2},
            {name: "Lassie", type: "dog", legs: 4},
            {name: "Spot", type: "dog", legs: 4},
            {name: "Polly", type: "bird", legs: 2},
            {name: "Fiona", type: "plants", legs: 0},
            ]);
var typeDimension = data.dimension(function(d){ return d.type; });
var t = typeDimension.filterFunction(function(d){ return d != "dog"; });

您将获得以下输出：

>> console.log(JSON.stringify(t.top(Infinity)));
>> [
    {"name":"Fiona","type":"plants","legs":0}
    {"name":"Alex","type":"human","legs":2},
    {"name":"Polly","type":"bird","legs":2}
   ]

通过Negation Crossfilter过滤

1 个答案: