How to apply aggregations in spark scala? : I have a data set `test1.txt`. It contain data like below

    2::1::3
    1::1::2
    1::2::2
    2::1::5
    2::1::4
    3::1::2
    3::1::1
    3::2::2

I have created data-frame using the below code. 

    case class Test(userId: Int, movieId: Int, rating: Float)
    def pRating(str: String): Rating = {
    val fields = str.split("::")
    assert(fields.size == 3)
    Test(fields(0).toInt, fields(1).toInt, fields(2).toFloat)
    }
    
    val ratings = spark.read.textFile("C:/Users/test/Desktop/test1.txt").map(pRating).toDF()
 2,1,3
    1,1,2
    1,2,2
    2,1,5
    2,1,4
    3,1,2
    3,1,1
    3,2,2

But I want to print output like below I.e. removing duplicate combinations and instead of `field(2) value 1.0`.

    1,1,2.0
    1,2,2.0
    2,1,12.0
    3,1,3.0
3,2,2.0   
Please help me on this, how can achieve this.