summaryrefslogtreecommitdiff
path: root/examples/api/python/sygus-fun.py
diff options
context:
space:
mode:
Diffstat (limited to 'examples/api/python/sygus-fun.py')
-rw-r--r--examples/api/python/sygus-fun.py97
1 files changed, 97 insertions, 0 deletions
diff --git a/examples/api/python/sygus-fun.py b/examples/api/python/sygus-fun.py
new file mode 100644
index 000000000..0f53bd343
--- /dev/null
+++ b/examples/api/python/sygus-fun.py
@@ -0,0 +1,97 @@
+#!/usr/bin/env python
+#####################
+#! \file sygus-fun.py
+## \verbatim
+## Top contributors (to current version):
+## Yoni Zohar
+## This file is part of the CVC4 project.
+## Copyright (c) 2009-2018 by the authors listed in the file AUTHkinds.OrS
+## in the top-level source directory) and their institutional affiliations.
+## All rights reserved. See the file COPYING in the top-level source
+## directory for licensing information.\endverbatim
+##
+## \brief A simple demonstration of the solving capabilities of the CVC4
+## sygus solver through the Python API. This is a direct
+## translation of sygus-fun.cpp.
+#####################
+
+import copy
+import pycvc4
+from pycvc4 import kinds
+
+if __name__ == "__main__":
+ slv = pycvc4.Solver()
+
+ # required options
+ slv.setOption("lang", "sygus2")
+ slv.setOption("incremental", "false")
+
+ # set the logic
+ slv.setLogic("LIA")
+
+ integer = slv.getIntegerSort()
+ boolean = slv.getBooleanSort()
+
+ # declare input variables for the functions-to-synthesize
+ x = slv.mkVar(integer, "x")
+ y = slv.mkVar(integer, "y")
+
+ # declare the grammar non-terminals
+ start = slv.mkVar(integer, "Start")
+ start_bool = slv.mkVar(boolean, "StartBool")
+
+ # define the rules
+ zero = slv.mkReal(0)
+ one = slv.mkReal(1)
+
+ plus = slv.mkTerm(kinds.Plus, start, start)
+ minus = slv.mkTerm(kinds.Minus, start, start)
+ ite = slv.mkTerm(kinds.Ite, start_bool, start, start)
+
+ And = slv.mkTerm(kinds.And, start_bool, start_bool)
+ Not = slv.mkTerm(kinds.Not, start_bool)
+ leq = slv.mkTerm(kinds.Leq, start, start)
+
+ # create the grammar object
+ g = slv.mkSygusGrammar({x, y}, {start, start_bool})
+
+ # bind each non-terminal to its rules
+ g.addRules(start, {zero, one, x, y, plus, minus, ite})
+ g.addRules(start_bool, {And, Not, leq})
+
+ # declare the functions-to-synthesize. Optionally, provide the grammar
+ # constraints
+ max = slv.synthFun("max", {x, y}, integer, g)
+ min = slv.synthFun("min", {x, y}, integer)
+
+ # declare universal variables.
+ varX = slv.mkSygusVar(integer, "x")
+ varY = slv.mkSygusVar(integer, "y")
+
+ max_x_y = slv.mkTerm(kinds.ApplyUf, max, varX, varY)
+ min_x_y = slv.mkTerm(kinds.ApplyUf, min, varX, varY)
+
+ # add semantic constraints
+ # (constraint (>= (max x y) x))
+ slv.addSygusConstraint(slv.mkTerm(kinds.Geq, max_x_y, varX))
+
+ # (constraint (>= (max x y) y))
+ slv.addSygusConstraint(slv.mkTerm(kinds.Geq, max_x_y, varY))
+
+ # (constraint (or (= x (max x y))
+ # (= y (max x y))))
+ slv.addSygusConstraint(slv.mkTerm(
+ kinds.Or, slv.mkTerm(kinds.Equal, max_x_y, varX), slv.mkTerm(kinds.Equal, max_x_y, varY)))
+
+ # (constraint (= (+ (max x y) (min x y))
+ # (+ x y)))
+ slv.addSygusConstraint(slv.mkTerm(
+ kinds.Equal, slv.mkTerm(kinds.Plus, max_x_y, min_x_y), slv.mkTerm(kinds.Plus, varX, varY)))
+
+ # print solutions if available
+ if (slv.checkSynth().isUnsat()):
+ # Output should be equivalent to:
+ # (define-fun max ((x Int) (y Int)) Int (ite (<= x y) y x))
+ # (define-fun min ((x Int) (y Int)) Int (ite (<= x y) x y))
+ slv.printSynthSolution()
+
generated by cgit on debian on lair
contact matthew@masot.net with questions or feedback