Ensure that piecewise constant values all have the same shape.

cara/models.py

@@ -142,6 +142,9 @@ class PiecewiseConstant:
             raise ValueError("transition_times should contain one more element than values")
         if tuple(sorted(set(self.transition_times))) != self.transition_times:
             raise ValueError("transition_times should not contain duplicated elements and should be sorted")
+        shapes = [np.array(v).shape for v in self.values]
+        if not all(shapes[0] == shape for shape in shapes):
+            raise ValueError("All values must have the same shape")
 
     def value(self, time) -> _VectorisedFloat:
         if time <= self.transition_times[0]:

cara/tests/models/test_piecewiseconstant.py

@@ -14,6 +14,13 @@ def test_piecewiseconstantfunction_wrongarguments():
     # unsorted transition times are not allowed
     pytest.raises(ValueError, models.PiecewiseConstant, (2, 0), (0, 0))
 
+    # If vectors, must all be same length.
+    with pytest.raises(ValueError, match="All values must have the same shape"):
+        models.PiecewiseConstant(
+            (0, 8, 16), (np.array([5, 7]), np.array([8, 9, 10])),
+        )
+
+
 
 @pytest.mark.parametrize(
     "time, expected_value",

cara/tests/test_ventilation.py

@@ -60,7 +60,9 @@ def test_hinged_window(baseline_hingedwindow, window_width,
         {'window_height': np.array([0.15, 0.20])},
         {'window_width': np.array([0.15, 0.20])},
         {'opening_length': np.array([0.15, 0.20])},
-        {'outside_temp': models.PiecewiseConstant((1, 2, 3), (np.array([20, 30]), 25))},
+        {'outside_temp': models.PiecewiseConstant(
+            (1, 2, 3), (np.array([20, 30]), np.array([25, 30]))),
+        },
         {'outside_temp': np.array([20, 30])},
         {'inside_temp': np.array([20, 30])},
     ]