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+#!/usr/bin/env python
+
+#####################
+#! \file linear_arith.py
+## \verbatim
+## Top contributors (to current version):
+## Makai Mann
+## This file is part of the CVC4 project.
+## Copyright (c) 2009-2018 by the authors listed in the file AUTHORS
+## 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
+## linear arithmetic solver through the Python API. This is a direct
+## translation of linear_arith-new.cpp.
+import pycvc4
+from pycvc4 import kinds
+
+if __name__ == "__main__":
+ slv = pycvc4.Solver()
+ slv.setLogic("QF_LIRA")
+
+ # Prove that if given x (Integer) and y (Real) and some constraints
+ # then the maximum value of y - x is 2/3
+
+ # Sorts
+ real = slv.getRealSort()
+ integer = slv.getIntegerSort()
+
+ # Variables
+ x = slv.mkConst(integer, "x")
+ y = slv.mkConst(real, "y")
+
+ # Constants
+ three = slv.mkReal(3)
+ neg2 = slv.mkReal(-2)
+ two_thirds = slv.mkReal(2, 3)
+
+ # Terms
+ three_y = slv.mkTerm(kinds.Mult, three, y)
+ diff = slv.mkTerm(kinds.Minus, y, x)
+
+ # Formulas
+ x_geq_3y = slv.mkTerm(kinds.Geq, x, three_y)
+ x_leq_y = slv.mkTerm(kinds.Leq, x ,y)
+ neg2_lt_x = slv.mkTerm(kinds.Lt, neg2, x)
+
+ assertions = slv.mkTerm(kinds.And, x_geq_3y, x_leq_y, neg2_lt_x)
+
+ print("Given the assertions", assertions)
+ slv.assertFormula(assertions)
+
+ slv.push()
+ diff_leq_two_thirds = slv.mkTerm(kinds.Leq, diff, two_thirds)
+ print("Prove that", diff_leq_two_thirds, "with CVC4")
+ print("CVC4 should report VALID")
+ print("Result from CVC4 is:",
+ slv.checkValidAssuming(diff_leq_two_thirds))
+ slv.pop()
+
+ print()
+
+ slv.push()
+ diff_is_two_thirds = slv.mkTerm(kinds.Equal, diff, two_thirds)
+ slv.assertFormula(diff_is_two_thirds)
+ print("Show that the assertions are consistent with\n", diff_is_two_thirds, "with CVC4")
+ print("CVC4 should report SAT")
+ print("Result from CVC4 is:", slv.checkSat())
+ slv.pop()
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