From e683a4e3845a8e5449bde3283571b2009b7dbdd8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Micha=C5=82=20Szynwelski?= <michal@szynwelski.pl>
Date: Tue, 14 Jun 2016 00:09:16 +0200
Subject: [PATCH] Optimization of row function.

---
 src/ObservationTable.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/ObservationTable.hs b/src/ObservationTable.hs
index a14a9fa..127c031 100644
--- a/src/ObservationTable.hs
+++ b/src/ObservationTable.hs
@@ -22,7 +22,7 @@ type Row i o = Fun [i] o
 -- `row is` denotes the data of a single row
 -- that is, the function E -> O
 row :: (NominalType i, NominalType o) => Table i o -> [i] -> Fun [i] o
-row t is = sum (apply (curry t) is)
+row t is = mapFilter (\((a,b),c) -> maybeIf (eq is a) (b,c)) t
 
 -- `rowa is a` is the row for the one letter extensions
 rowa :: (NominalType i, NominalType o) => Table i o -> [i] -> i -> Fun [i] o