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1 // Part 2 about Alcohol-Consumption Worldwide |
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2 //============================================ |
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3 |
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4 |
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5 // (1) Complete the function that is given a list of floats |
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6 // and calculuates the indices for when to buy the commodity |
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7 // and when to sell |
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8 |
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9 |
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10 // (2) Complete the ``get webpage'' function that takes a |
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11 // a stock symbol as argument and queries the Yahoo server |
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12 // at |
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13 // http://ichart.yahoo.com/table.csv?s=<<insert stock symbol>> |
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14 // |
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15 // This servive returns a CSV-list that needs to be separated into |
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16 // a list of strings. |
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17 |
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18 import io.Source |
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19 import scala.util._ |
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20 |
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21 def get_csv_page(url: String) : List[String] = |
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22 Source.fromURL(url)("ISO-8859-1").getLines.toList |
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23 |
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24 def get_csv_file(file: String) : List[String] = |
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25 Source.fromFile(file)("ISO-8859-1").getLines.toList |
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26 |
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27 |
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28 val url_alcohol = |
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29 "https://raw.githubusercontent.com/fivethirtyeight/data/master/alcohol-consumption/drinks.csv" |
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30 |
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31 val file_population = |
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32 "population.cvs" |
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33 |
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34 get_csv_page(url_alcohol) |
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35 get_csv_file(file_population) |
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36 |
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37 get_csv_page(url_alcohol).size |
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38 get_csv_file(file_population).size |
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39 |
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40 val alcs = get_csv_page(url_alcohol) |
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41 val pops = get_csv_file(file_population) |
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42 |
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43 |
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44 def process_alcs(lines: List[String]) : List[(String, Double)] = |
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45 for (l <- lines) yield { |
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46 val entries = l.split(",").toList |
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47 (entries(0), entries(4).toDouble) |
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48 } |
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49 |
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50 def process_pops(lines: List[String]) : Map[String, Long] = |
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51 (for (l <- lines) yield { |
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52 val entries = l.split(",").toList |
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53 (entries(0), entries(1).toLong) |
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54 }).toMap |
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55 |
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56 |
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57 def sorted_country_consumption() : List[(String, Long)] = { |
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58 val alcs2 = process_alcs(alcs.drop(1)) |
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59 val pops2 = process_pops(pops.drop(1)) |
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60 val cons_list = |
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61 for ((cname, cons) <- alcs2; if pops2.isDefinedAt(cname)) yield (cname, (cons * pops2(cname)).toLong) |
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62 cons_list.sortBy(_._2).reverse |
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63 } |
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64 |
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65 sorted_country_consumption().take(10) |
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66 sorted_country_consumption().size |
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67 |
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68 consumption.foreach { println } |
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69 |
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70 def percentage(n: Int) : (Long, Long, Double) = { |
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71 val cons_list = sorted_country_consumption() |
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72 val sum_n = cons_list.take(n).map(_._2).sum |
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73 val sum_all = cons_list.map(_._2).sum |
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74 val perc = (sum_n.toDouble / sum_all.toDouble) * 100.0 |
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75 (sum_all, sum_n, perc) |
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76 } |
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77 |
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78 percentage(164) |
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79 |