A.count B.reduceByKeyAndWidow C.countByValue D.reduceByKey
单项选择题MLlib供的分布式矩阵中,不包含行、列索引信息的矩阵类型是()
A.RowMatrix B.IndexedRowMatrix C.Matrix D.CoordinateMatrix
单项选择题MLlib中创建稀疏矩阵((0.0,2.0),(3.0,0.0),(0.0,6.0))的语句是()
A.val dm:Matrix=Matrices.dense(3,2,Array(0.0,3.0,0.0,2.0,0.0,6.0)) B.val dm:Matrix=Matrices.sparse(3,2,Array(0.0,2.0,3.0,0.0,0.0,6.0)) C.val sm:Matrix=Matrices.sparse(3,2,Array(0,1,2),Array(1,0,1),Array(2,3,6)) D.val sm:Matrix=Matrices.dense(3,2,Array(0,1,2),Array(1,0,1),Array(2,3,6))
单项选择题基于密集向量(1.0,0.0,3.0)创建一个LabledPoint,设其标识值为1.0,以下正确的选项为()
A.val pos=LabeledPoint(1.0,Vectors.dense(1.0,0.0,3.0)) B.val pos=LabeledPoint(1.0,(1.0,0.0,3.0)) C.val pos=LabeledPoint(Vectors.dense(1.0,0.0,3.0),1.0) D.val pos=LabeledPoint((1.0,0.0,3.0),1.0)
单项选择题val rdd=sc.parallelize(1to10).filter(_%2==0)rdd.collect上述代码的执行结果为()
A.Array(1,2,3,4,5,6,7,8,9,10) B.Array(1,3,5,7,9) C.Array(2,4,6,8,10) D.Array(1,10)
单项选择题val rdd=sc.parallelize(List(( Tom ,2),( Lee ,5),( Lee ,6),(“Tom”,7)))rdd.reduceByKey((x,y)=>x+y).collect上述代码的执行结果为()
A.Array((1,2),(3,10)) B.Array((9,“Tom”),(11,“Lee”)) C.Array((“Tom”,9),(“Lee”,11)) D.Array((“Tom”,2,7),(“Lee”,5,6))