1 // Advanvced Part 3 about a really dumb investment strategy  | 
     1 // Part 2 and 3 about a really dumb investment strategy  | 
     2 //==========================================================  | 
     2 //======================================================  | 
     3   | 
     3   | 
     4 object CW6c { | 
     4 //object CW6b { // for purposes of generating a jar | 
     5   | 
     5   | 
     6   | 
     6   | 
     7 //two test portfolios  | 
     7 //two test portfolios  | 
     8   | 
     8   | 
     9 val blchip_portfolio = List("GOOG", "AAPL", "MSFT", "IBM", "FB", "AMZN", "BIDU") | 
     9 val blchip_portfolio = List("GOOG", "AAPL", "MSFT", "IBM", "FB", "AMZN", "BIDU") | 
    10 val rstate_portfolio = List("PLD", "PSA", "AMT", "AIV", "AVB", "BXP", "CCI",  | 
    10 val rstate_portfolio = List("PLD", "PSA", "AMT", "AIV", "AVB", "BXP", "CCI",  | 
    11                             "DLR", "EQIX", "EQR", "ESS", "EXR", "FRT", "GGP", "HCP")   | 
    11                             "DLR", "EQIX", "EQR", "ESS", "EXR", "FRT", "HCP")   | 
    12   | 
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    13 // (1) The function below should obtain the first trading price  | 
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    14 // for a stock symbol by using the query  | 
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    15 //  | 
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    16 //    http://ichart.yahoo.com/table.csv?s=<<symbol>>&a=0&b=1&c=<<year>>&d=1&e=1&f=<<year>>   | 
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    17 //   | 
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    18 // and extracting the first January Adjusted Close price in a year.  | 
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    19   | 
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    20   | 
    12   | 
    21 import io.Source  | 
    13 import io.Source  | 
    22 import scala.util._  | 
    14 import scala.util._  | 
    23   | 
    15   | 
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    16 // (1) The function below takes a stock symbol and a year as arguments.  | 
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    17 //     It should read the corresponding CSV-file and reads the January   | 
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    18 //     data from the given year. The data should be collected in a list of  | 
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    19 //     strings for each line in the CSV-file.  | 
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    20   | 
    24 def get_january_data(symbol: String, year: Int) : List[String] =   | 
    21 def get_january_data(symbol: String, year: Int) : List[String] =   | 
    25   Source.fromFile(symbol ++ ".csv").getLines.toList.filter(_.startsWith(year.toString))  | 
    22   Source.fromFile(symbol ++ ".csv")("ISO-8859-1").getLines.toList.filter(_.startsWith(year.toString)) | 
    26   | 
    23   | 
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    24   | 
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    25 //test cases  | 
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    26 //blchip_portfolio.map(get_january_data(_, 2018))  | 
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    27 //rstate_portfolio.map(get_january_data(_, 2018))  | 
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    28   | 
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    29 //get_january_data("GOOG", 1980) | 
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    30 //get_january_data("GOOG", 2010) | 
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    31 //get_january_data("FB", 2014) | 
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    32   | 
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    33 //get_january_data("PLD", 1980) | 
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    34 //get_january_data("EQIX", 2010) | 
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    35 //get_january_data("ESS", 2014) | 
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    36   | 
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    37   | 
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    38 // (2) From the output of the get_january_data function, the next function   | 
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    39 //     should extract the first line (if it exists) and the corresponding  | 
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    40 //     first trading price in that year with type Option[Double]. If no line   | 
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    41 //     is generated by get_january_data then the result is None; Some if   | 
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    42 //     there is a price.  | 
    27   | 
    43   | 
    28 def get_first_price(symbol: String, year: Int) : Option[Double] = { | 
    44 def get_first_price(symbol: String, year: Int) : Option[Double] = { | 
    29   val data = Try(Some(get_january_data(symbol, year).head)) getOrElse None   | 
    45   val data = Try(Some(get_january_data(symbol, year).head)) getOrElse None   | 
    30   data.map(_.split(",").toList(1).toDouble) | 
    46   data.map(_.split(",").toList(1).toDouble) | 
    31 }  | 
    47 }  | 
    32   | 
    48   | 
    33 get_first_price("GOOG", 1980) | 
    49 //test cases  | 
    34 get_first_price("GOOG", 2010) | 
    50 //get_first_price("GOOG", 1980) | 
    35 get_first_price("FB", 2014) | 
    51 //get_first_price("GOOG", 2010) | 
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    52 //get_first_price("FB", 2014) | 
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    53   | 
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    54 /*  | 
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    55 for (i <- 1978 to 2018) { | 
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    56   println(blchip_portfolio.map(get_first_price(_, i)))  | 
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    57 }  | 
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    58   | 
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    59 for (i <- 1978 to 2018) { | 
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    60   println(rstate_portfolio.map(get_first_price(_, i)))  | 
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    61 }  | 
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    62 */   | 
    36   | 
    63   | 
    37   | 
    64   | 
    38 // Complete the function below that obtains all first prices  | 
    65 // (3) Complete the function below that obtains all first prices  | 
    39 // for the stock symbols from a portfolio for the given  | 
    66 //     for the stock symbols from a portfolio (list of strings) and   | 
    40 // range of years  | 
    67 //     for the given range of years. The inner lists are for the  | 
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    68 //     stock symbols and the outer list for the years.  | 
    41   | 
    69   | 
    42 def get_prices(portfolio: List[String], years: Range): List[List[Option[Double]]] =   | 
    70 def get_prices(portfolio: List[String], years: Range): List[List[Option[Double]]] =   | 
    43   for (year <- years.toList) yield  | 
    71   for (year <- years.toList) yield  | 
    44     for (symbol <- portfolio) yield get_first_price(symbol, year)  | 
    72     for (symbol <- portfolio) yield get_first_price(symbol, year)  | 
    45   | 
    73   | 
    46   | 
    74   | 
    47 // test case  | 
    75 //test cases  | 
    48 val p_fb = get_prices(List("FB"), 2012 to 2014) | 
    76 //val p_fb = get_prices(List("FB"), 2012 to 2014) | 
    49 val p = get_prices(List("GOOG", "AAPL"), 2010 to 2012) | 
    77 //val p = get_prices(List("GOOG", "AAPL"), 2010 to 2012) | 
    50   | 
    78   | 
    51 val tt = get_prices(List("BIDU"), 2004 to 2008) | 
    79 //val tt = get_prices(List("BIDU"), 2004 to 2008) | 
    52   | 
    80   | 
    53 // (2) The first function below calculates the change factor (delta) between  | 
    81   | 
    54 // a price in year n and a price in year n+1. The second function calculates  | 
    82 //==============================================  | 
    55 // all change factors for all prices (from a portfolio).  | 
    83 // Do not change anything below, unless you want   | 
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    84 // to submit the file for the advanced part 3!  | 
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    85 //==============================================  | 
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    86   | 
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    87   | 
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    88 // (4) The function below calculates the change factor (delta) between  | 
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    89 //     a price in year n and a price in year n + 1.   | 
    56   | 
    90   | 
    57 def get_delta(price_old: Option[Double], price_new: Option[Double]) : Option[Double] = { | 
    91 def get_delta(price_old: Option[Double], price_new: Option[Double]) : Option[Double] = { | 
    58   (price_old, price_new) match { | 
    92   (price_old, price_new) match { | 
    59     case (Some(x), Some(y)) => Some((y - x) / x)  | 
    93     case (Some(x), Some(y)) => Some((y - x) / x)  | 
    60     case _ => None  | 
    94     case _ => None  | 
    61   }  | 
    95   }  | 
    62 }  | 
    96 }  | 
    63   | 
    97   | 
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    98   | 
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    99 // (5) The next function calculates all change factors for all prices (from a   | 
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   100 //     portfolio). The input to this function are the nested lists created by   | 
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   101 //     get_prices above.  | 
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   102   | 
    64 def get_deltas(data: List[List[Option[Double]]]):  List[List[Option[Double]]] =  | 
   103 def get_deltas(data: List[List[Option[Double]]]):  List[List[Option[Double]]] =  | 
    65   for (i <- (0 until (data.length - 1)).toList) yield   | 
   104   for (i <- (0 until (data.length - 1)).toList) yield   | 
    66     for (j <- (0 until (data(0).length)).toList) yield get_delta(data(i)(j), data(i + 1)(j))  | 
   105     for (j <- (0 until (data(0).length)).toList) yield get_delta(data(i)(j), data(i + 1)(j))  | 
    67   | 
   106   | 
    68   | 
   107   | 
    69 // test case using the prices calculated above  | 
   108 // test case using the prices calculated above  | 
    70 val d = get_deltas(p)  | 
   109 //val d = get_deltas(p)  | 
    71 val ttd = get_deltas(tt)  | 
   110 //val ttd = get_deltas(tt)  | 
    72   | 
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    73 // (3) Write a function that given change factors, a starting balance and a year  | 
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    74 // calculates the yearly yield, i.e. new balanace, according to our dump investment   | 
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    75 // strategy. Another function calculates given the same data calculates the  | 
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    76 // compound yield up to a given year. Finally a function combines all   | 
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    77 // calculations by taking a portfolio, a range of years and a start balance  | 
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    78 // as arguments.  | 
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    79   | 
   111   | 
    80   | 
   112   | 
    81 def yearly_yield(data: List[List[Option[Double]]], balance: Long, year: Int): Long = { | 
   113 // (6) Write a function that given change factors, a starting balance and an index,  | 
    82   val somes = data(year).flatten  | 
   114 //     calculates the yearly yield, i.e. new balance, according to our dumb investment   | 
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   115 //     strategy. Index points to a year in the data list.  | 
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   116   | 
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   117 def yearly_yield(data: List[List[Option[Double]]], balance: Long, index: Int): Long = { | 
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   118   val somes = data(index).flatten  | 
    83   val somes_length = somes.length  | 
   119   val somes_length = somes.length  | 
    84   if (somes_length == 0) balance  | 
   120   if (somes_length == 0) balance  | 
    85   else { | 
   121   else { | 
    86     val portion: Double = balance.toDouble / somes_length.toDouble  | 
   122     val portion: Double = balance.toDouble / somes_length.toDouble  | 
    87     balance + (for (x <- somes) yield (x * portion)).sum.toLong  | 
   123     balance + (for (x <- somes) yield (x * portion)).sum.toLong  | 
    88   }  | 
   124   }  | 
    89 }  | 
   125 }  | 
    90   | 
   126   | 
    91 def compound_yield(data: List[List[Option[Double]]], balance: Long, year: Int): Long = { | 
   127   | 
    92   if (year >= data.length) balance else { | 
   128 // (7) Write a function compound_yield that calculates the overall balance for a   | 
    93     val new_balance = yearly_yield(data, balance, year)  | 
   129 //     range of years where in each year the yearly profit is compounded to the new   | 
    94     compound_yield(data, new_balance, year + 1)  | 
   130 //     balances and then re-invested into our portfolio. For this use the function and   | 
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   131 //     results generated under (6). The function investment calls compound_yield  | 
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   132 //     with the appropriate deltas and the first index.  | 
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   133   | 
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   134   | 
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   135 def compound_yield(data: List[List[Option[Double]]], balance: Long, index: Int): Long = { | 
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   136   if (index >= data.length) balance else { | 
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   137     val new_balance = yearly_yield(data, balance, index)  | 
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   138     compound_yield(data, new_balance, index + 1)  | 
    95   }  | 
   139   }  | 
    96 }  | 
   140 }  | 
    97   | 
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    98 //yearly_yield(d, 100, 0)  | 
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    99 //compound_yield(d.take(6), 100, 0)  | 
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   100   | 
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   101 //test case  | 
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   102 //yearly_yield(d, 100, 0)  | 
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   103 //yearly_yield(d, 225, 1)  | 
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   104 //yearly_yield(d, 246, 2)  | 
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   105 //yearly_yield(d, 466, 3)  | 
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   106 //yearly_yield(d, 218, 4)  | 
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   107   | 
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   108 //yearly_yield(d, 100, 0)  | 
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   109 //yearly_yield(d, 125, 1)  | 
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   110   | 
   141   | 
   111 def investment(portfolio: List[String], years: Range, start_balance: Long): Long = { | 
   142 def investment(portfolio: List[String], years: Range, start_balance: Long): Long = { | 
   112   compound_yield(get_deltas(get_prices(portfolio, years)), start_balance, 0)  | 
   143   compound_yield(get_deltas(get_prices(portfolio, years)), start_balance, 0)  | 
   113 }  | 
   144 }  | 
   114   | 
   145   | 
   115 /*  | 
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   116 val q1 = get_deltas(get_prices(List("GOOG", "AAPL", "BIDU"), 2000 to 2017)) | 
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   117 yearly_yield(q1, 100, 0)  | 
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   118 yearly_yield(q1, 100, 1)  | 
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   119 yearly_yield(q1, 100, 2)  | 
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   120 yearly_yield(q1, 100, 3)  | 
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   121 yearly_yield(q1, 100, 4)  | 
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   122 yearly_yield(q1, 100, 5)  | 
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   123 yearly_yield(q1, 100, 6)  | 
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   124   | 
   146   | 
   125 investment(List("GOOG", "AAPL", "BIDU"), 2004 to 2017, 100) | 
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   126 val one = get_deltas(get_prices(rstate_portfolio, 1978 to 1984))  | 
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   127 val two = get_deltas(get_prices(blchip_portfolio, 1978 to 1984))  | 
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   128   | 
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   129 val one_full = get_deltas(get_prices(rstate_portfolio, 1978 to 2017))  | 
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   130 val two_full = get_deltas(get_prices(blchip_portfolio, 1978 to 2017))  | 
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   131   | 
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   132 one_full.map(_.flatten).map(_.sum).sum  | 
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   133 two_full.map(_.flatten).map(_.sum).sum  | 
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   134   | 
   147   | 
   135 //test cases for the two portfolios given above  | 
   148 //test cases for the two portfolios given above  | 
   136   | 
   149   | 
   137 //println("Real data: " + investment(rstate_portfolio, 1978 to 2017, 100)) | 
   150 //println("Real data: " + investment(rstate_portfolio, 1978 to 2018, 100)) | 
   138 //println("Blue data: " + investment(blchip_portfolio, 1978 to 2017, 100)) | 
   151 //println("Blue data: " + investment(blchip_portfolio, 1978 to 2018, 100)) | 
   139   | 
   152   | 
   140 for (i <- 2000 to 2017) { | 
   153 //}  | 
   141   println("Year " + i) | 
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   142   //println("Real data: " + investment(rstate_portfolio, 1978 to i, 100)) | 
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   143   //println("Blue data: " + investment(blchip_portfolio, 1978 to i, 100)) | 
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   144   println("test: " + investment(List("GOOG", "AAPL", "BIDU"), 2000 to i, 100)) | 
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   145 }  | 
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   146   | 
   154   | 
   147   | 
   155   | 
   148 */   | 
   156   | 
   149 //1984  | 
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   150 //1992  | 
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   151 }  | 
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