diff -r b5b6ed38c2f2 -r 682611a0fb89 main_templates2/danube.scala --- a/main_templates2/danube.scala Mon Nov 02 13:10:02 2020 +0000 +++ b/main_templates2/danube.scala Wed Nov 04 14:46:03 2020 +0000 @@ -157,18 +157,30 @@ // => Nil (there are three ratings for this movie in ratings.csv but they are not positive) -// If you want to calculate the recommendations for all movies, -// then use this code (it will take a few seconds calculation time). + +// (7) Calculate the recommendations for all movies according to +// what the recommendations function in (6) produces (this +// can take a few seconds). Put all recommendations into a list +// (of strings) and count how often the strings occur in +// this list. This produces a list of string-int pairs, +// where the first component is the movie name and the second +// is the number of how many times they were recommended. +// Sort all the pairs according to the number +// of times they were recommended (most recommended movie name +// first). -//val all = for (name <- movie_names.map(_._1)) yield { -// recommendations(ratings_map, movies_map, name) -//} +def most_recommended(recs: Map[String, List[String]], + movs: Map[String, String]) : List[(String, Int)] = ??? + -// helper functions -//List().take(2) -//List(1).take(2) -//List(1,2).take(2) -//List(1,2,3).take(2) +// testcase +// +//most_recommended(ratings_map, movies_map).take(3) +// => +// List((Matrix,698), +// (Star Wars: Episode IV - A New Hope (1977),402), +// (Jerry Maguire (1996),382)) + }