40 import io.Source

    41  

    41 import scala.util._

    42 val ls6_urban = (10 to 500 by 10).map(_.toString).toList

    43 val ls7_urban = ls6_urban zip ls6_urban.tail

    44 val ls8_urban = ls7_urban ::: ls7_urban.reverse

    43 def urban_get_csv_file(name: String) : List[String] = {

    46 assert(urban_ck(ls8_urban)) 

    44   val csv = Source.fromFile(name)

    45   csv.mkString.split("\n").toList.drop(1)

    46 }

    47 

    48 def urban_process_ratings(lines: List[String]) : List[(String, String)] = {

    49   for (cols <- lines.map(_.split(",").toList); 

    50        if (cols(2).toFloat >= 4)) yield (cols(0), cols(1))  

    51 }

    52 

    53 val urban_ratings = urban_process_ratings(urban_get_csv_file("ratings.csv").take(1000))

    54 

    55 assert(urban_ck(urban_ratings))