diff -r fd03a2f06286 -r 1b0f1573c27c templates/alcohol.scala --- a/templates/alcohol.scala Tue Nov 07 14:17:21 2017 +0000 +++ b/templates/alcohol.scala Wed Nov 08 02:06:54 2017 +0000 @@ -6,64 +6,60 @@ import io.Source import scala.util._ -def get_csv_page(url: String) : List[String] = - Source.fromURL(url)("ISO-8859-1").getLines.toList - -def get_csv_file(file: String) : List[String] = - Source.fromFile(file)("ISO-8859-1").getLines.toList - - val url_alcohol = "https://raw.githubusercontent.com/fivethirtyeight/data/master/alcohol-consumption/drinks.csv" val file_population = "population.csv" -get_csv_page(url_alcohol) -get_csv_file(file_population) -get_csv_page(url_alcohol).size -get_csv_file(file_population).size +//(1) Complete the get_csv_page function below. It takes the URL-string +// as argument and generates a list of strings corresponing to each +// line in the csv list. The URL url_alcohol is one possible argument. -val alcs = get_csv_page(url_alcohol) -val pops = get_csv_file(file_population) +//def get_csv_page(url: String) : List[String] = ... -def process_alcs(lines: List[String]) : List[(String, Double)] = - for (l <- lines) yield { - val entries = l.split(",").toList - (entries(0), entries(4).toDouble) - } +// Complete the get_csv_file function below. It takes a file-string +// as argument and reads the content of the given file. Like above +// it should generates a list of strings corresponing to each +// line in the csv-list. The filename file_population is one possible +// argument. -def process_pops(lines: List[String]) : Map[String, Long] = - (for (l <- lines) yield { - val entries = l.split(",").toList - (entries(0), entries(1).toLong) - }).toMap +//def get_csv_file(file: String) : List[String] = ... + -def sorted_country_consumption() : List[(String, Long)] = { - val alcs2 = process_alcs(alcs.drop(1)) - val pops2 = process_pops(pops.drop(1)) - val cons_list = - for ((cname, cons) <- alcs2; - if pops2.isDefinedAt(cname)) yield (cname, (cons * pops2(cname)).toLong) - cons_list.sortBy(_._2).reverse -} +//(2) Complete the functions that process the csv-lists. For +// process_alcs extract the country name (as String) and the +// pure alcohol consumption (as Double). For process_pops +// generate a Map of Strings (country names) to Long numbers +// (population size). -sorted_country_consumption().take(10) -sorted_country_consumption().size +//def process_alcs(lines: List[String]) : List[(String, Double)] = ... -def percentage(n: Int) : (Long, Long, Double) = { - val cons_list = sorted_country_consumption() - val sum_n = cons_list.take(n).map(_._2).sum - val sum_all = cons_list.map(_._2).sum - val perc = (sum_n.toDouble / sum_all.toDouble) * 100.0 - (sum_all, sum_n, perc) -} +//def process_pops(lines: List[String]) : Map[String, Long] = ... + -percentage(10) -percentage(164) +//(3) Calculate for each country the overall alcohol_consumption using +// the data from the alcohol list and the population sizes list. You +// should only include countries on the alcohol list that are also +// (with the exact name) on the population sizes list. Note that +// the spelling of some names in the alcohol list differs from the +// population sizes list. Sort the resulting list according to the +// country with the highest alcohol consumption to the country +// with the lowest alcohol consumption. + +//def sorted_country_consumption() : List[(String, Long)] = ... + + +// Calculate the world consumption of pure alcohol of all countries, which +// should be the first element in the tuple below. The second element is +// the overall consumption of the first n countries in the sorted list +// from above; and finally the double should be the percentage of the +// first n countries of the the world consumption of alcohol. + +//def percentage(n: Int) : (Long, Long, Double) = ... }