X-Git-Url: https://scm.cri.mines-paristech.fr/git/linpy.git/blobdiff_plain/51e97eade63b2f4c7b500feb503436cc4a886e59..809c5b59db7b6be224146b8d957453a0f9fb43aa:/examples/nsad2010.py

diff --git a/examples/nsad2010.py b/examples/nsad2010.py
index f310f9d..3de2ebd 100755
--- a/examples/nsad2010.py
+++ b/examples/nsad2010.py
@@ -1,23 +1,14 @@
 #!/usr/bin/env python3
 
-"""
-    This file is part of Linpy.
+# This is an implementation of the algorithm described in
+#
+# [ACI10] C. Ancourt, F. Coelho and F. Irigoin, A modular static analysis
+# approach to affine loop invariants detection (2010), pp. 3 - 16, NSAD 2010.
+#
+# to compute the transitive closure of an affine transformer. A refined version
+# of this algorithm is implemented in PIPS.
 
-    Linpy 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 3 of the License, or
-    (at your option) any later version.
-
-    Linpy 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 Linpy.  If not, see <http://www.gnu.org/licenses/>.
-"""
-
-from pypol import *
+from linpy import Dummy, Eq, Ge, Polyhedron, symbols
 
 
 class Transformer:
@@ -37,7 +28,8 @@ class Transformer:
         delta_symbols = [symbol.asdummy() for symbol in self.range_symbols]
         k = Dummy('k')
         polyhedron = self.polyhedron
-        for x, xprime, dx in zip(self.range_symbols, self.domain_symbols, delta_symbols):
+        for x, xprime, dx in zip(
+                self.range_symbols, self.domain_symbols, delta_symbols):
             polyhedron &= Eq(dx, xprime - x)
         polyhedron = polyhedron.project(self.symbols)
         equalities, inequalities = [], []
@@ -49,17 +41,16 @@ class Transformer:
             inequalities.append(inequality)
         polyhedron = Polyhedron(equalities, inequalities) & Ge(k, 0)
         polyhedron = polyhedron.project([k])
-        for x, xprime, dx in zip(self.range_symbols, self.domain_symbols, delta_symbols):
+        for x, xprime, dx in zip(
+                self.range_symbols, self.domain_symbols, delta_symbols):
             polyhedron &= Eq(dx, xprime - x)
         polyhedron = polyhedron.project(delta_symbols)
         return Transformer(polyhedron, self.range_symbols, self.domain_symbols)
 
 
 if __name__ == '__main__':
-    i, iprime, j, jprime = symbols("i i' j j'")
-    transformer = Transformer(Eq(iprime, i + 2) & Eq(jprime, j + 1),
-        [i, j], [iprime, jprime])
+    i0, i, j0, j = symbols('i0 i j0 j')
+    transformer = Transformer(Eq(i, i0 + 2) & Eq(j, j0 + 1),
+                              [i0, j0], [i, j])
     print('T  =', transformer.polyhedron)
     print('T* =', transformer.star().polyhedron)
-    
-# Copyright 2014 MINES ParisTech