A DataVec reduction op for averaging a list of coordinates

GeoAveragingReduction.scala

// our reduction op class that we will need shortly
class GeoAveragingReduction(columnOutputName: String="AveragedLatLon") extends AggregableColumnReduction {
        
    override def reduceColumn(columnData: java.util.List[Writable]): Writable = {
        val coordinates = columnData.map( d => d.toString.split(",") ).map{ case Array(lat,lon) => (lat.toDouble,lon.toDouble) }
        val (lat,lon) = coordinates.reduceLeft(avgCoordinates)
        new Text(s"""$lat,$lon""")
    }

    private def avgCoordinates(latlon1: (Double, Double), latlon2: (Double, Double)): (Double, Double) = {
        var (lat1,lon1) = latlon1
        var (lat2,lon2) = latlon2
        var dLon = Math.toRadians(lon2 - lon1)

        // convert to radians
        lat1 = Math.toRadians(lat1)
        lat2 = Math.toRadians(lat2)
        lon1 = Math.toRadians(lon1)

        val Bx = Math.cos(lat2) * Math.cos(dLon)
        val By = Math.cos(lat2) * Math.sin(dLon)
        val lat3 = Math.atan2(Math.sin(lat1) + Math.sin(lat2), Math.sqrt((Math.cos(lat1) + Bx) * (Math.cos(lat1) + Bx) + By * By))
        val lon3 = lon1 + Math.atan2(By, Math.cos(lat1) + Bx)

        (Math.toDegrees(lat3), Math.toDegrees(lon3))
    }

    override def getColumnOutputMetaData(x$1: String,x$2: org.datavec.api.transform.metadata.ColumnMetaData): org.datavec.api.transform.metadata.ColumnMetaData = {
        new StringMetaData(outputColumnName)
    }
    def getColumnOutputName(columnInputName: String): String = columnOutputName

    def columnName(): String = ???
    def columnNames(): Array[String] = ???
    def getInputSchema(): org.datavec.api.transform.schema.Schema = ???
    def outputColumnName(): String = ???
    def outputColumnNames(): Array[String] = ???
    def setInputSchema(x$1: org.datavec.api.transform.schema.Schema): Unit = ???
    def transform(x$1: org.datavec.api.transform.schema.Schema): org.datavec.api.transform.schema.Schema = ???
    }

    class AverageCoordinatesOp[T] extends IAggregableReduceOp[T, Writable] {
    def combine[W:>IAggregableReduceOp[T, Writable]](W accu): Unit = {

    }
}