--- a/progs/drumb.scala Wed Nov 09 00:52:08 2016 +0000
+++ b/progs/drumb.scala Wed Nov 09 01:02:41 2016 +0000
@@ -8,67 +8,34 @@
"DLR", "EQIX", "EQR", "ESS", "EXR", "FRT", "GGP", "HCP")
-import io.Source
-import scala.util._
+def get_yahoo_page(url: String): Option[List[String]] = ...
-def get_yahoo_page(url: String): Option[List[String]] = {
- Try(Some(Source.fromURL(url)("ISO-8859-1").getLines.toList)).
- getOrElse { None }
-}
+def get_first_price(symbol: String, year: Int): Option[Double] = ...
-def get_first_price(symbol: String, year: Int): Option[Double] = {
- //println(s"download..${symbol} at ${year}")
- val year_string = year.toString
- val date_string = s"&a=0&b=1&c=${year_string}&d=1&e=1&f=${year_string}"
- val url = """http://ichart.yahoo.com/table.csv?s=""" + symbol + date_string
- val data = get_yahoo_page(url)
- data.map(_.last.split(",").toList(6).toDouble)
-}
+def get_prices(portfolio: List[String], years: Range): List[List[Option[Double]]] = ...
-def get_prices(portfolio: List[String], years: Range): List[List[Option[Double]]] =
- for (year <- years.toList) yield
- for (symbol <- portfolio) yield get_first_price(symbol, year)
-get_prices(List("GOOG", "AAPL"), 2010 to 2012)
+//val p = get_prices(List("GOOG", "AAPL"), 2010 to 2012)
-def get_delta(price_old: Option[Double], price_new: Option[Double]): Option[Double] = {
- (price_old, price_new) match {
- case (Some(x), Some(y)) => Some((y - x) / x)
- case _ => None
- }
-}
-
-def get_deltas(data: List[List[Option[Double]]]): List[List[Option[Double]]] =
- for (i <- (0 until (data.length - 1)).toList) yield
- for (j <- (0 until (data(0).length)).toList) yield get_delta(data(i)(j), data(i + 1)(j))
+def get_delta(price_old: Option[Double], price_new: Option[Double]): Option[Double] = ...
-def yearly_yield(data: List[List[Option[Double]]], balance: Long, year: Int): Long = {
- val somes = data(year).flatten
- val somes_length = somes.length
- if (somes_length == 0) balance
- else {
- val portion: Double = balance / somes_length
- balance + (for (x <- somes) yield (x * portion)).sum.toLong
- }
-}
+def get_deltas(data: List[List[Option[Double]]]): List[List[Option[Double]]] = ...
-def compound_yield(data: List[List[Option[Double]]], balance: Long, year: Int): Long = {
- if (year >= data.length) balance else {
- val new_balance = yearly_yield(data, balance, year)
- compound_yield(data, new_balance, year + 1)
- }
-}
+//val d = get_deltas(p)
-val p = get_prices(List("GOOG", "AAPL"), 2010 to 2012)
-val d = get_deltas(p)
-yearly_yield(d, 100, 0)
-
-def investment(portfolio: List[String], years: Range, start_balance: Long): Long = {
- compound_yield(get_deltas(get_prices(portfolio, years)), start_balance, 0)
-}
-println("Real data: " + investment(rstate_portfolio, 1978 to 2016, 100))
-println("Blue data: " + investment(blchip_portfolio, 1978 to 2016, 100))
+def yearly_yield(data: List[List[Option[Double]]], balance: Long, year: Int): Long = ...
+
+//yearly_yield(d, 100, 0)
+
+def compound_yield(data: List[List[Option[Double]]], balance: Long, year: Int): Long = ...
+
+def investment(portfolio: List[String], years: Range, start_balance: Long): Long = ...
+
+
+//investment(rstate_portfolio, 1978 to 2016, 100)
+//investment(blchip_portfolio, 1978 to 2016, 100)
+