反馈:Apache Spark决策树的可视化

Question

我在Apache Spark中遇到的一个问题是可视化决策树.

我可以使用生产树DecisionTree.trainClassifier.我可以使用以下方法获得一些基本输出:

print(model.toDebugString())

但理想情况下,目前的输出:

    If (feature 0 <= -35.0)
  If (feature 24 <= 176.0)
    Predict: 2.1
  If (feature 24 = 176.0)
    Predict: 4.2
  Else (feature 24 > 176.0)
    Predict: 6.3
Else (feature 0 > -35.0)
  If (feature 24 <= 11.0)
    Predict: 4.5
  Else (feature 24 > 11.0)
    Predict: 10.2

可以输出为JSON或可解析的东西,以便我们可以在D3 Visualization库中进行分层.使用上面的例子......

{
"node": [
    {
        "name":"node1",
        "rule":"feature 0 <= -35.0",
            "children":[
                {
                  "name":"node2",
                  "rule":"feature 24 <= 176.0",
                  "children":[
                      {
                      "name":"node4",
                      "rule":"feature 20 < 116.0",
                      "predict":  2.1
                      },
                      {
                      "name":"node5",
                      "rule":"feature 20 = 116.0",
                      "predict": 4.2
                      },
                      {
                      "name":"node5",
                      "rule":"feature 20 > 116.0",
                      "predict": 6.3
                      }
                  ]                    
                },
                {
                "name":"node3",
                "rule":"feature 0 > -35.0",
                  "children":[
                      {
                      "name":"node7",
                      "rule":"feature 3 <= 11.0",
                      "predict": 4.5
                      },
                      {
                      "name":"node8",
                      "rule":"feature 3 > 11.0",
                      "predict": 10.2
                      }
                  ]                                        
                }

            ]
    }
]

}