用Casbah查询深度嵌套的MongoDB对象[斯卡拉]

{'_id': ObjectId('589df735be9fa2077dc5bb2e'), 
'name': 'train.2', 
'samples': [{'processed': {'eulerAngles': [1.946705159018607, 
              -0.01405100477972897, 
              0.02015610032297892]}, 
       'raw': {'accel': [0.01548936311155558, 
           0.0002011665492318571, 
           0.02126962691545486], 
         'gyro': [0.06626824289560318, 
           0.1328225582838058, 
           0.001385239884257317]}, 
       'timestamp': '2017-02-10T17:24:04.283Z'}, 
      {'processed': {'eulerAngles': [1.948553665755181, 
              -0.01403613777322358, 
              0.01932380767991558]}, 
       'raw': {'accel': [0.01380419824272394, 
           -0.001462434651330113, 
           0.01273023523390293], 
         'gyro': [0.09209229052066803, 
           0.07342914491891861, 
           0.01548820454627275]}, 
       'timestamp': '2017-02-10T17:24:04.293Z'}}]}

对于样本数组中的每个样本，我需要提取数组加速度。我写了下面的代码用Casbah查询深度嵌套的MongoDB对象[斯卡拉]

val el = db("samples").findOne(MongoDBObject("name" -> name)) 
    var t_series_seq: Array[Array[Double]] = Array() 
    for (m <- el.get("samples")) t_series_seq :+ m("raw")("accel")

这是返回value foreach is not a member of AnyRef。我需要告诉el.get（“samples”）类型，但我不知道如何判断它是一个复杂的Map对象。

来源

2017-02-17 FranGoitia

好吧，所以Casbah文档非常糟糕。实际上，我阅读了专门在Scala中使用MongoDB和Data Scala的章节。

我的代码将是如下：

val dbSamples = db("samples").find(MongoDBObject("name" -> name)) 
var timesSeries: Array[TimeSeries] = Array() 
for (s <- dbSamples) { 
    var tSeries_seq: Array[Array[Double]] = Array() 
    val measures = s.getAs[List[DBObject]]("samples").get 
    for (m <- measures) { 
    println(m.getAs[DBObject]("raw").get.getAs[List[Double]]("accel").get.toArray) 
    tSeries_seq = tSeries_seq :+ m.getAs[DBObject]("raw").get.getAs[List[Double]]("accel").get.toArray 
    } 
    timesSeries = timesSeries :+ new TimeSeries(tSeries_seq, s.getAs[Integer]("valid").get) 
} 
timesSeries

来源

2017-02-20 19:32:19 FranGoitia

用Casbah查询深度嵌套的MongoDB对象[斯卡拉]

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