1 |
1 |
2 import CW7b._ |
2 import CW7b._ |
3 |
3 |
4 // first test |
4 // first test |
5 |
5 |
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6 def urban_groupById(ratings: List[(String, String)], |
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7 m: Map[String, List[String]]) : Map[String, List[String]] = ratings match { |
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8 case Nil => m |
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9 case (id, mov) :: rest => { |
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10 val old_ratings = m.getOrElse (id, Nil) |
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11 val new_ratings = m + (id -> (mov :: old_ratings)) |
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12 urban_groupById(rest, new_ratings) |
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13 } |
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14 } |
6 |
15 |
7 def urban_groupById(ratings: List[(String, String)]) = |
16 //def urban_groupById(ratings: List[(String, String)]) = |
8 ratings.groupBy(_._1).view.mapValues(_.map(_._2)).toMap |
17 // ratings.groupBy(_._1).view.mapValues(_.map(_._2)).toMap |
9 |
18 |
10 def urban_get_csv_file(name: String) : List[String] = { |
19 def urban_get_csv_file(name: String) : List[String] = { |
11 import io.Source |
20 import io.Source |
12 import scala.util._ |
21 import scala.util._ |
13 val csv = Source.fromFile(name) |
22 val csv = Source.fromFile(name)("ISO-8859-1") |
14 csv.mkString.split("\n").toList.drop(1) |
23 csv.mkString.split("\n").toList.drop(1) |
15 } |
24 } |
16 |
25 |
17 def urban_process_ratings(lines: List[String]) : List[(String, String)] = { |
26 def urban_process_ratings(lines: List[String]) : List[(String, String)] = { |
18 for (cols <- lines.map(_.split(",").toList); |
27 for (cols <- lines.map(_.split(",").toList); |
19 if (cols(2).toFloat >= 4)) yield (cols(0), cols(1)) |
28 if (cols(2).toInt >= 4)) yield (cols(0), cols(1)) |
20 } |
29 } |
21 |
30 |
22 def urban_process_movies(lines: List[String]) : List[(String, String)] = { |
31 def urban_process_movies(lines: List[String]) : List[(String, String)] = { |
23 for (cols <- lines.map(_.split(",").toList)) yield (cols(0), cols(1)) |
32 for (cols <- lines.map(_.split(",").toList)) yield (cols(0), cols(1)) |
24 } |
33 } |
25 |
34 |
26 |
35 |
27 val urban_good_ratings = process_ratings(urban_get_csv_file("ratings.csv")) |
36 val urban_good_ratings = urban_process_ratings(urban_get_csv_file("ratings.csv")) |
28 val urban_movie_names = process_movies(urban_get_csv_file("movies.csv")).toMap |
37 val urban_movie_names = urban_process_movies(urban_get_csv_file("movies.csv")).toMap |
29 |
38 |
30 val urban_ratings_map = urban_groupById(urban_good_ratings) |
39 val urban_ratings_map = urban_groupById(urban_good_ratings, Map()) |
31 |
40 |
32 assert((for (n <- List("1", "2", "3", "4", "5")) yield { |
41 assert((for (n <- List("1", "2", "3", "4", "5")) yield { |
33 recommendations(urban_ratings_map, urban_movie_names, n).length |
42 recommendations(urban_ratings_map, urban_movie_names, n).length |
34 }) == List(2, 2, 2, 0, 2)) |
43 }) == List(2, 2, 2, 0, 2)) |
35 |
44 |