Issue #58: Expose state vector element names

Author: Mark2000

src/bsk_rl/envs/general_satellite_tasking/scenario/sat_observations.py

@@ -53,7 +53,14 @@ def obs_dict(self):
     @property
     def obs_ndarray(self):
         """Numpy vector observation format."""
-        return vectorize_nested_dict(self.obs_dict)
+        _, obs = vectorize_nested_dict(self.obs_dict)
+        return obs
+
+    @property
+    def obs_array_keys(self):
+        """Utility to get the keys of the obs_ndarray."""
+        keys, _ = vectorize_nested_dict(self.obs_dict)
+        return keys
 
     @property
     def obs_list(self):

src/bsk_rl/envs/general_satellite_tasking/utils/functional.py

@@ -77,18 +77,25 @@ def collect_default_args(object: object) -> dict[str, Any]:
     return defaults
 
 
-def vectorize_nested_dict(dictionary: dict) -> np.ndarray:
-    """Flattens a dictionary of dicts, arrays, and scalars into a single vector."""
+def vectorize_nested_dict(dictionary: dict) -> tuple[list[str], np.ndarray]:
+    """Flattens a dictionary of dictionaries, arrays, and scalars into a vector."""
+    keys = list(dictionary.keys())
     values = list(dictionary.values())
     for i, value in enumerate(values):
         if isinstance(value, np.ndarray):
             values[i] = value.flatten()
+            keys[i] = [keys[i] + f"[{j}]" for j in range(len(value.flatten()))]
+        elif isinstance(value, list):
+            keys[i] = [keys[i] + f"[{j}]" for j in range(len(value))]
         elif isinstance(value, (float, int)):
             values[i] = [value]
+            keys[i] = [keys[i]]
         elif isinstance(value, dict):
-            values[i] = vectorize_nested_dict(value)
+            prepend = keys[i]
+            keys[i], values[i] = vectorize_nested_dict(value)
+            keys[i] = [prepend + "." + key for key in keys[i]]
 
-    return np.concatenate(values)
+    return list(np.concatenate(keys)), np.concatenate(values)
 
 
 def aliveness_checker(func: Callable[..., bool]) -> Callable[..., bool]:

tests/unittest/envs/general_satellite_tasking/utils/test_functional.py

@@ -76,14 +76,24 @@ class C13(self.C1, self.C3):
 
 
 @pytest.mark.parametrize(
-    "input,output",
+    "input,outkeys,outvec",
     [
-        ({"a": np.array([1]), "b": 2, "c": [3]}, np.array([1, 2, 3])),
-        ({"a": {"b": 1, "c": 2}, "d": 3}, np.array([1, 2, 3])),
+        (
+            {"alpha": np.array([1]), "b": 2, "c": [3]},
+            ["alpha[0]", "b", "c[0]"],
+            np.array([1, 2, 3]),
+        ),
+        (
+            {"a": {"b": 1, "charlie": 2}, "d": 3},
+            ["a.b", "a.charlie", "d"],
+            np.array([1, 2, 3]),
+        ),
     ],
 )
-def test_vectorize_nested_dict(input, output):
-    assert np.equal(output, functional.vectorize_nested_dict(input)).all()
+def test_vectorize_nested_dict(input, outkeys, outvec):
+    keys, vec = functional.vectorize_nested_dict(input)
+    assert np.equal(outvec, vec).all()
+    assert outkeys == keys
 
 
 class TestAlivenessChecker: