diff -r ff8d075842d5 -r 28c8e17ab83a marking/drumb_test3.scala
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/marking/drumb_test3.scala	Fri Dec 02 16:45:31 2016 +0000
@@ -0,0 +1,27 @@
+//println("starting test now")
+
+import scala.concurrent._
+import scala.concurrent.duration._
+import ExecutionContext.Implicits.global
+import scala.language.postfixOps 
+
+val test_data = List(List(Some(71.539941), None), List(Some(76.974614), None), 
+                     List(Some(65.226685), Some(6.35)), List(Some(78.354649), Some(12.241)), 
+                     List(Some(85.517645), Some(38.188)))
+
+val test_deltas = List(List(Some(0.07596697626574789), None), 
+                       List(Some(-0.152620823795232), None), 
+                       List(Some(0.20126676681483952), Some(0.9277165354330709)), 
+                       List(Some(0.09141762603007778), Some(2.119679764725104)))
+
+lazy val f = Future {
+  assert((yearly_yield(test_deltas, 100, 0) - 107).abs <= 2)
+  assert((yearly_yield(test_deltas, 100, 1) - 85).abs <= 2)
+  assert((yearly_yield(test_deltas, 100, 2) - 156).abs <= 2)
+  assert((yearly_yield(test_deltas, 100, 3) - 210).abs <= 2)
+  assert((investment(List("IBM", "BIDU"), 2004 to 2008, 100) - 298).abs <= 10)
+}
+
+
+Await.result(f, 180 second)
+