update base libraries; improve sat internals

ortools/linear_solver/samples/mip_var_array.py

@@ -10,7 +10,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-"""Integer programming examples that show how to use the APIs."""
+"""MIP example that uses a variable array."""
 # [START program]
 # [START import]
 from __future__ import print_function
@@ -23,7 +23,6 @@ from ortools.linear_solver import pywraplp
 def create_data_model():
     """Stores the data for the problem."""
     data = {}
-    # Locations in block units
     data['constraint_coeffs'] = [
         [5, 7, 9, 2, 1],
         [18, 4, -9, 10, 12],
@@ -50,6 +49,7 @@ def main():
     solver = pywraplp.Solver('simple_mip_program',
                              pywraplp.Solver.CBC_MIXED_INTEGER_PROGRAMMING)
     # [END solver]
+
     # [START variables]
     infinity = solver.infinity()
     x = {}

ortools/linear_solver/samples/simple_mip_program.py

@@ -50,20 +50,17 @@ def main():
     # [END objective]
 
     # [START solve]
-    result_status = solver.Solve()
-    # The problem has an optimal solution.
-    assert result_status == pywraplp.Solver.OPTIMAL
-
-    # The solution looks legit (when using solvers others than
-    # GLOP_LINEAR_PROGRAMMING, verifying the solution is highly recommended!).
-    assert solver.VerifySolution(1e-7, True)
+    status = solver.Solve()
     # [END solve]
 
     # [START print_solution]
-    print('Solution:')
-    print('Objective value =', solver.Objective().Value())
-    print('x =', x.solution_value())
-    print('y =', y.solution_value())
+    if status == pywraplp.Solver.OPTIMAL:
+        print('Solution:')
+        print('Objective value =', solver.Objective().Value())
+        print('x =', x.solution_value())
+        print('y =', y.solution_value())
+    else:
+        print('The problem does not have an optimal solution.')
     # [END print_solution]
 
     # [START advanced]