[lmi-commits] [lmi] master f786840 2/2: Avoid catastrophic cancellation

[Greg Chicares]

branch: master
commit f7868401e65436296a442e64a1bd3bda27782887
Author: Gregory W. Chicares <gchicares@sbcglobal.net>
Commit: Gregory W. Chicares <gchicares@sbcglobal.net>

    Avoid catastrophic cancellation
    
    An experimental modification elsewhere unexpected caused the necessary
    premium to be -7.10543e-17, which violated assertions downstream (at
    inception, for a case with a 1035 exchange).
---
 ihs_avmly.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ihs_avmly.cpp b/ihs_avmly.cpp
index 22b1cc5..1d1466e 100644
--- a/ihs_avmly.cpp
+++ b/ihs_avmly.cpp
@@ -202,7 +202,7 @@ void AccountValue::DoMonthDR()
         gross_1035 = External1035Amount + Internal1035Amount;
         }
     double necessary_premium = std::min
-        (GrossPmts[Month] - gross_1035
+        (material_difference(GrossPmts[Month], gross_1035)
         ,max_necessary_premium
         );
     double unnecessary_premium = material_difference