Remove sample.after_mip

miplearn/components/objective.py

@@ -95,13 +95,12 @@ class ObjectiveValueComponent(Component):
 
         # Labels
         y: Dict[Hashable, List[List[float]]] = {}
-        if sample.after_mip is not None:
+        mip_lower_bound = sample.get("mip_lower_bound")
-            mip_stats = sample.after_mip.mip_solve
+        mip_upper_bound = sample.get("mip_upper_bound")
-            assert mip_stats is not None
+        if mip_lower_bound is not None:
-            if mip_stats.mip_lower_bound is not None:
+            y["Lower bound"] = [[mip_lower_bound]]
-                y["Lower bound"] = [[mip_stats.mip_lower_bound]]
+        if mip_upper_bound is not None:
-            if mip_stats.mip_upper_bound is not None:
+            y["Upper bound"] = [[mip_upper_bound]]
-                y["Upper bound"] = [[mip_stats.mip_upper_bound]]
 
         return x, y
 
@@ -111,9 +110,6 @@ class ObjectiveValueComponent(Component):
         instance: Instance,
         sample: Sample,
     ) -> Dict[Hashable, Dict[str, float]]:
-        assert sample.after_mip is not None
-        assert sample.after_mip.mip_solve is not None
-
         def compare(y_pred: float, y_actual: float) -> Dict[str, float]:
             err = np.round(abs(y_pred - y_actual), 8)
             return {
@@ -125,8 +121,8 @@ class ObjectiveValueComponent(Component):
 
         result: Dict[Hashable, Dict[str, float]] = {}
         pred = self.sample_predict(sample)
-        actual_ub = sample.after_mip.mip_solve.mip_upper_bound
+        actual_ub = sample.get("mip_upper_bound")
-        actual_lb = sample.after_mip.mip_solve.mip_lower_bound
+        actual_lb = sample.get("mip_lower_bound")
         if actual_ub is not None:
             result["Upper bound"] = compare(pred["Upper bound"], actual_ub)
         if actual_lb is not None:

miplearn/components/primal.py

@@ -155,6 +155,7 @@ class PrimalSolutionComponent(Component):
         assert sample.after_load.variables is not None
         assert sample.after_load.variables.names is not None
         assert sample.after_load.variables.categories is not None
+        mip_var_values = sample.get("mip_var_values")
 
         for (i, var_name) in enumerate(sample.after_load.variables.names):
             # Initialize categories
@@ -174,10 +175,8 @@ class PrimalSolutionComponent(Component):
             x[category].append(features)
 
             # Labels
-            if sample.after_mip is not None:
+            if mip_var_values is not None:
-                assert sample.after_mip.variables is not None
+                opt_value = mip_var_values[i]
-                assert sample.after_mip.variables.values is not None
-                opt_value = sample.after_mip.variables.values[i]
                 assert opt_value is not None
                 assert 0.0 - 1e-5 <= opt_value <= 1.0 + 1e-5, (
                     f"Variable {var_name} has non-binary value {opt_value} in the "
@@ -194,14 +193,13 @@ class PrimalSolutionComponent(Component):
         _: Optional[Instance],
         sample: Sample,
     ) -> Dict[Hashable, Dict[str, float]]:
-        assert sample.after_mip is not None
+        mip_var_values = sample.get("mip_var_values")
-        assert sample.after_mip.variables is not None
+        var_names = sample.get("var_names")
-        assert sample.after_mip.variables.values is not None
+        assert mip_var_values is not None
-        assert sample.after_mip.variables.names is not None
+        assert var_names is not None
 
         solution_actual = {
-            var_name: sample.after_mip.variables.values[i]
+            var_name: mip_var_values[i] for (i, var_name) in enumerate(var_names)
-            for (i, var_name) in enumerate(sample.after_mip.variables.names)
         }
         solution_pred = self.sample_predict(sample)
         vars_all, vars_one, vars_zero = set(), set(), set()

miplearn/features.py

@@ -148,7 +148,6 @@ class Sample:
         self,
         after_load: Optional[Features] = None,
         after_lp: Optional[Features] = None,
-        after_mip: Optional[Features] = None,
         data: Optional[Dict[str, Any]] = None,
     ) -> None:
         if data is None:
@@ -156,7 +155,6 @@ class Sample:
         self._data: Dict[str, Any] = data
         self.after_load = after_load
         self.after_lp = after_lp
-        self.after_mip = after_mip
 
     def get(self, key: str) -> Optional[Any]:
         if key in self._data:

miplearn/solvers/learning.py

@@ -210,6 +210,7 @@ class LearningSolver:
             # -------------------------------------------------------
             logger.info("Extracting features (after-lp)...")
             initial_time = time.time()
+            self.extractor.extract_after_lp_features(self.internal_solver, sample)
             features = self.extractor.extract(
                 instance,
                 self.internal_solver,
@@ -219,6 +220,8 @@ class LearningSolver:
                 "Features (after-lp) extracted in %.2f seconds"
                 % (time.time() - initial_time)
             )
+            for (k, v) in lp_stats.__dict__.items():
+                sample.put(k, v)
             features.lp_solve = lp_stats
             sample.after_lp = features
 
@@ -282,17 +285,13 @@ class LearningSolver:
         # -------------------------------------------------------
         logger.info("Extracting features (after-mip)...")
         initial_time = time.time()
-        features = self.extractor.extract(
+        self.extractor.extract_after_mip_features(self.internal_solver, sample)
-            instance,
+        for (k, v) in mip_stats.__dict__.items():
-            self.internal_solver,
+            sample.put(k, v)
-            with_static=False,
-        )
         logger.info(
             "Features (after-mip) extracted in %.2f seconds"
             % (time.time() - initial_time)
         )
-        features.mip_solve = mip_stats
-        sample.after_mip = features
 
         # After-solve callbacks
         # -------------------------------------------------------

tests/components/test_objective.py

@@ -25,12 +25,10 @@ def sample() -> Sample:
         after_lp=Features(
             lp_solve=LPSolveStats(),
         ),
-        after_mip=Features(
+        data={
-            mip_solve=MIPSolveStats(
+            "mip_lower_bound": 1.0,
-                mip_lower_bound=1.0,
+            "mip_upper_bound": 2.0,
-                mip_upper_bound=2.0,
+        },
-            )
-        ),
     )
     sample.after_load.instance.to_list = Mock(return_value=[1.0, 2.0])  # type: ignore
     sample.after_lp.lp_solve.to_list = Mock(return_value=[3.0])  # type: ignore

tests/components/test_primal.py

@@ -36,12 +36,10 @@ def sample() -> Sample:
         after_lp=Features(
             variables=VariableFeatures(),
         ),
-        after_mip=Features(
+        data={
-            variables=VariableFeatures(
+            "var_names": ["x[0]", "x[1]", "x[2]", "x[3]"],
-                names=["x[0]", "x[1]", "x[2]", "x[3]"],
+            "mip_var_values": [0.0, 1.0, 1.0, 0.0],
-                values=[0.0, 1.0, 1.0, 0.0],
+        },
-            )
-        ),
     )
     sample.after_load.instance.to_list = Mock(return_value=[5.0])  # type: ignore
     sample.after_load.variables.to_list = Mock(  # type:ignore

tests/problems/test_tsp.py

@@ -41,14 +41,9 @@ def test_instance() -> None:
     solver.solve(instance)
     assert len(instance.get_samples()) == 1
     sample = instance.get_samples()[0]
-    assert sample.after_mip is not None
+    assert sample.get("mip_var_values") == [1.0, 0.0, 1.0, 1.0, 0.0, 1.0]
-    features = sample.after_mip
+    assert sample.get("mip_lower_bound") == 4.0
-    assert features is not None
+    assert sample.get("mip_upper_bound") == 4.0
-    assert features.variables is not None
-    assert features.variables.values == [1.0, 0.0, 1.0, 1.0, 0.0, 1.0]
-    assert features.mip_solve is not None
-    assert features.mip_solve.mip_lower_bound == 4.0
-    assert features.mip_solve.mip_upper_bound == 4.0
 
 
 def test_subtour() -> None:
@@ -73,10 +68,7 @@ def test_subtour() -> None:
     lazy_enforced = sample.get("lazy_enforced")
     assert lazy_enforced is not None
     assert len(lazy_enforced) > 0
-    assert sample.after_mip is not None
+    assert sample.get("mip_var_values") == [
-    features = sample.after_mip
-    assert features.variables is not None
-    assert features.variables.values == [
         1.0,
         0.0,
         0.0,

tests/solvers/test_learning_solver.py

@@ -38,25 +38,18 @@ def test_learning_solver(
             assert len(instance.get_samples()) > 0
             sample = instance.get_samples()[0]
 
-            after_mip = sample.after_mip
+            assert sample.get("mip_var_values") == [1.0, 0.0, 1.0, 1.0, 61.0]
-            assert after_mip is not None
+            assert sample.get("mip_lower_bound") == 1183.0
-            assert after_mip.variables is not None
+            assert sample.get("mip_upper_bound") == 1183.0
-            assert after_mip.variables.values == [1.0, 0.0, 1.0, 1.0, 61.0]
+            mip_log = sample.get("mip_log")
-            assert after_mip.mip_solve is not None
+            assert mip_log is not None
-            assert after_mip.mip_solve.mip_lower_bound == 1183.0
+            assert len(mip_log) > 100
-            assert after_mip.mip_solve.mip_upper_bound == 1183.0
+
-            assert after_mip.mip_solve.mip_log is not None
+            assert_equals(sample.get("lp_var_values"), [1.0, 0.923077, 1.0, 0.0, 67.0])
-            assert len(after_mip.mip_solve.mip_log) > 100
+            assert_equals(sample.get("lp_value"), 1287.923077)
-
+            lp_log = sample.get("lp_log")
-            after_lp = sample.after_lp
+            assert lp_log is not None
-            assert after_lp is not None
+            assert len(lp_log) > 100
-            assert after_lp.variables is not None
-            assert_equals(after_lp.variables.values, [1.0, 0.923077, 1.0, 0.0, 67.0])
-            assert after_lp.lp_solve is not None
-            assert after_lp.lp_solve.lp_value is not None
-            assert round(after_lp.lp_solve.lp_value, 3) == 1287.923
-            assert after_lp.lp_solve.lp_log is not None
-            assert len(after_lp.lp_solve.lp_log) > 100
 
             solver.fit([instance], n_jobs=4)
             solver.solve(instance)