--- a
+++ b/inst/__subSingleInt__.m
@@ -0,0 +1,25 @@
+## Copyright (C) 2008 simone pernice
+## 
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 2 of the License, or
+## (at your option) any later version.
+## 
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+## 
+## You should have received a copy of the GNU General Public License
+## along with this program; if not, write to the Free Software
+## Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+
+## __subSingleInt__ subtract intervals returning int1-int2
+
+## Author: simone pernice
+## Created: 2008-08-18
+
+function ret = __subSingleInt__ (int1, int2)
+  int2 = __negateSingleInt__ (int2);
+  ret = __addSingleInt__ (int1, int2);
+endfunction