Extract _load_mp_vectors_by_party helper and fix cache key

- Extract shared helper that both load_party_axis_scores and
  load_party_mp_vectors delegate to, eliminating ~40 lines of
  duplicated DB query + vector parsing code
- Remove dead code in load_party_axis_scores that queried mp_metadata
  twice (first without ORDER BY, then again with ORDER BY, overwriting)
- Fix _cached_bootstrap_cis parameter: remove _ prefix so Streamlit
  actually hashes the input dict instead of caching with no key

explorer.py

@@ -397,116 +397,27 @@ def compute_party_discipline(
                 pass
 
 
-@st.cache_data(show_spinner="Partijposities op SVD-assen laden…")
+def _load_mp_vectors_by_party(db_path: str) -> Dict[str, List[np.ndarray]]:
-def load_party_axis_scores(db_path: str) -> Dict[str, List[float]]:
+    """Load individual MP SVD vectors grouped by party.
-    """Return per-party SVD vectors, computed as mean of individual MP vectors.
 
-    Loads individual MP rows (entity_id LIKE '%,%') from window='current_parliament',
+    Queries mp_metadata for the mp→party mapping (latest assignment during the
-    assigns each MP their party using the dominant party from mp_votes, then
+    current parliament), normalises party names, loads SVD vectors from the
-    averages SVD vectors per party.
+    ``current_parliament`` window, and filters to CURRENT_PARLIAMENT_PARTIES.
-
-    This matches the political compass data source (also averages individual MPs),
-    so axis rankings are consistent between the SVD tab and the compass.
-
-    Returns:
-        {party_name: [float * k]}  — k = 50, mean over all MPs in that party.
-    """
-    try:
-        con = duckdb.connect(database=db_path, read_only=True)
-
-        # Build mp → party mapping from mp_metadata (most recent party during current parliament).
-        # mp_metadata format: mp_name like "Van Baarle, S.R.T.", party = "GroenLinks-PvdA"
-        # We take the party record with the latest `van` date (most recent assignment).
-        meta_rows = con.execute(
-            "SELECT mp_name, party FROM mp_metadata "
-            "WHERE van >= '2023-11-22' OR tot_en_met IS NULL OR tot_en_met >= '2023-11-22'"
-        ).fetchall()
-        # For MPs with multiple records (party switches), keep the one with latest van date.
-        # Simple approach: last-write-wins per mp_name after sorting by van ascending.
-        mp_party_raw: Dict[str, str] = {}
-        for mp_name, party in meta_rows:
-            if mp_name and party:
-                mp_party_raw[mp_name] = party  # later rows (after ORDER BY van) win
-
-        # Re-query ordered so latest van wins reliably
-        meta_ordered = con.execute(
-            "SELECT mp_name, party FROM mp_metadata "
-            "WHERE van >= '2023-11-22' OR tot_en_met IS NULL OR tot_en_met >= '2023-11-22' "
-            "ORDER BY van ASC"
-        ).fetchall()
-        mp_party_raw = {}
-        for mp_name, party in meta_ordered:
-            if mp_name and party:
-                mp_party_raw[mp_name] = party
-
-        # Normalize party names to canonical abbreviations
-        mp_party: Dict[str, str] = {}
-        for mp_name, party in mp_party_raw.items():
-            canonical = _PARTY_NORMALIZE.get(party, party)
-            mp_party[mp_name] = canonical
-
-        # Individual MP vectors from current_parliament
-        rows = con.execute(
-            "SELECT entity_id, vector FROM svd_vectors "
-            "WHERE entity_type='mp' AND window_id='current_parliament'"
-        ).fetchall()
-
-        party_vecs: Dict[str, list] = {}
-        for entity_id, raw_vec in rows:
-            party = mp_party.get(entity_id)
-            if party is None or party not in CURRENT_PARLIAMENT_PARTIES:
-                continue
-            if isinstance(raw_vec, str):
-                vec = json.loads(raw_vec)
-            elif isinstance(raw_vec, (bytes, bytearray)):
-                vec = json.loads(raw_vec.decode())
-            elif isinstance(raw_vec, list):
-                vec = raw_vec
-            else:
-                try:
-                    vec = list(raw_vec)
-                except Exception:
-                    continue
-            fvec = [float(v) if v is not None else 0.0 for v in vec]
-            party_vecs.setdefault(party, []).append(fvec)
-
-        # Average vectors per party
-        result: Dict[str, List[float]] = {}
-        for party, vecs in party_vecs.items():
-            result[party] = np.array(vecs).mean(axis=0).tolist()
-        return result
-    except Exception:
-        logger.exception("Failed to load party axis scores")
-        return {}
-    finally:
-        try:
-            con.close()
-        except Exception:
-            pass
-
-
-@st.cache_data(show_spinner="Partij-MP vectoren laden…")
-def load_party_mp_vectors(db_path: str) -> Dict[str, List[np.ndarray]]:
-    """Return per-party lists of individual MP SVD vectors.
-
-    Same MP→party mapping as load_party_axis_scores(), but returns the raw
-    per-MP vectors instead of averaging them. Suitable for bootstrap CI
-    computation.
 
     Returns:
         {party_name: [np.ndarray(50,), ...]}  — one array per MP.
     """
+    con = duckdb.connect(database=db_path, read_only=True)
     try:
-        con = duckdb.connect(database=db_path, read_only=True)
+        # Build mp → party mapping.  ORDER BY van ASC so latest assignment wins
-
+        # via last-write-wins when an MP switched party.
-        # Build mp → party mapping (same logic as load_party_axis_scores)
+        meta_rows = con.execute(
-        meta_ordered = con.execute(
             "SELECT mp_name, party FROM mp_metadata "
             "WHERE van >= '2023-11-22' OR tot_en_met IS NULL OR tot_en_met >= '2023-11-22' "
             "ORDER BY van ASC"
         ).fetchall()
         mp_party: Dict[str, str] = {}
-        for mp_name, party in meta_ordered:
+        for mp_name, party in meta_rows:
             if mp_name and party:
                 mp_party[mp_name] = _PARTY_NORMALIZE.get(party, party)
 
@@ -536,9 +447,6 @@ def load_party_mp_vectors(db_path: str) -> Dict[str, List[np.ndarray]]:
             party_vecs.setdefault(party, []).append(fvec)
 
         return party_vecs
-    except Exception:
-        logger.exception("Failed to load party MP vectors")
-        return {}
     finally:
         try:
             con.close()
@@ -546,14 +454,52 @@ def load_party_mp_vectors(db_path: str) -> Dict[str, List[np.ndarray]]:
             pass
 
 
+@st.cache_data(show_spinner="Partijposities op SVD-assen laden…")
+def load_party_axis_scores(db_path: str) -> Dict[str, List[float]]:
+    """Return per-party SVD vectors, computed as mean of individual MP vectors.
+
+    Loads individual MP rows from window='current_parliament', assigns each MP
+    their party, then averages SVD vectors per party.
+
+    Returns:
+        {party_name: [float * k]}  — k = 50, mean over all MPs in that party.
+    """
+    try:
+        party_vecs = _load_mp_vectors_by_party(db_path)
+        return {
+            party: np.array(vecs).mean(axis=0).tolist()
+            for party, vecs in party_vecs.items()
+        }
+    except Exception:
+        logger.exception("Failed to load party axis scores")
+        return {}
+
+
+@st.cache_data(show_spinner="Partij-MP vectoren laden…")
+def load_party_mp_vectors(db_path: str) -> Dict[str, List[np.ndarray]]:
+    """Return per-party lists of individual MP SVD vectors.
+
+    Same MP→party mapping as load_party_axis_scores(), suitable for bootstrap
+    CI computation.
+
+    Returns:
+        {party_name: [np.ndarray(50,), ...]}  — one array per MP.
+    """
+    try:
+        return _load_mp_vectors_by_party(db_path)
+    except Exception:
+        logger.exception("Failed to load party MP vectors")
+        return {}
+
+
 @st.cache_data(show_spinner="Bootstrap CI berekenen…")
 def _cached_bootstrap_cis(
-    _party_mp_vectors: Dict[str, List[np.ndarray]],
+    party_mp_vectors: Dict[str, List[np.ndarray]],
 ) -> Dict[str, Dict]:
     """Thin caching wrapper around compute_party_bootstrap_cis."""
     from analysis.political_axis import compute_party_bootstrap_cis
 
-    return compute_party_bootstrap_cis(_party_mp_vectors)
+    return compute_party_bootstrap_cis(party_mp_vectors)
 
 
 @st.cache_data(show_spinner="Scree-plot laden…")