Fix movement tracking and add melodic threshold weights

- Add movement tracking to edges: {source: {destination, cent_difference}}
- Fix movement map to handle multiple changing pitches with permutations
- Remove melodic threshold from graph building (apply in weight calculation)
- Add melodic_threshold_min/max to weight config
- Add CLI args --melodic-min and --melodic-max

compact_sets.py

@@ -367,7 +367,6 @@ class HarmonicSpace:
         chords: set[Chord],
         symdiff_min: int = 2,
         symdiff_max: int = 2,
-        melodic_threshold_cents: float | None = None,
     ) -> nx.MultiDiGraph:
         """
         Build a voice leading graph from a set of chords.
@@ -376,7 +375,6 @@ class HarmonicSpace:
             chords: Set of Chord objects
             symdiff_min: Minimum symmetric difference between chords
             symdiff_max: Maximum symmetric difference between chords
-            melodic_threshold_cents: If set, filter edges by max pitch movement
 
         Returns:
             NetworkX MultiDiGraph
@@ -391,34 +389,49 @@ class HarmonicSpace:
 
         # Add edges based on local morphological constraints
         for c1, c2 in combinations(chords, 2):
-            edges = self._find_valid_edges(
+            edges = self._find_valid_edges(c1, c2, symdiff_range)
-                c1, c2, symdiff_range, melodic_threshold_cents
-            )
             for edge_data in edges:
-                trans, weight = edge_data
+                trans, weight, movements = edge_data
-                graph.add_edge(c1, c2, transposition=trans, weight=weight)
+                graph.add_edge(
+                    c1, c2, transposition=trans, weight=weight, movements=movements
+                )
                 graph.add_edge(
                     c2,
                     c1,
                     transposition=self._invert_transposition(trans),
                     weight=weight,
+                    movements=self._reverse_movements(movements),
                 )
 
         return graph
 
+    def _reverse_movements(self, movements: dict) -> dict:
+        """Reverse the movement mappings."""
+        reversed_movements = {}
+        for src, data in movements.items():
+            dst = data["destination"]
+            reversed_movements[dst] = {
+                "destination": src,
+                "cent_difference": -data["cent_difference"],
+            }
+        return reversed_movements
+
     def _find_valid_edges(
         self,
         c1: Chord,
         c2: Chord,
         symdiff_range: tuple[int, int],
-        melodic_threshold_cents: float | None,
+    ) -> list[tuple[Pitch, float, dict]]:
-    ) -> list[tuple[Pitch, float]]:
         """
         Find all valid edges between two chords.
 
         Tests all transpositions of c2 to find ones that satisfy
         the symmetric difference constraint AND each changing pitch
         is connected (adjacent) to a pitch in the previous chord.
+
+        Returns:
+            List of (transposition, weight, movements) tuples.
+            movements is a dict: {source_pitch: {"destination": dest_pitch, "cent_difference": cents}}
         """
         edges = []
 
@@ -444,18 +457,99 @@ class HarmonicSpace:
                 if not voice_lead_ok:
                     continue
 
-                # Check melodic threshold if specified
+                # Build all valid movement maps (one per permutation of changing pitches)
-                if melodic_threshold_cents is not None:
+                movement_maps = self._build_movement_maps(
-                    if not self._check_melodic_threshold(
+                    c1.pitches, c2_transposed.pitches
-                        c1.pitches, c2_transposed.pitches, melodic_threshold_cents
+                )
-                    ):
-                        continue
 
-                # Valid edge found
+                # Create one edge per movement map
-                edges.append((trans, 1.0))
+                for movements in movement_maps:
+                    edges.append((trans, 1.0, movements))
 
         return edges
 
+    def _build_movement_maps(
+        self, c1_pitches: tuple[Pitch, ...], c2_transposed_pitches: tuple[Pitch, ...]
+    ) -> list[dict]:
+        """
+        Build all valid movement maps for c1 -> c2_transposed.
+
+        A movement map shows which pitch in c1 maps to which pitch in c2,
+        including the cent difference for each movement.
+
+        Returns:
+            List of movement maps. Each map is {source_pitch: {"destination": dest_pitch, "cent_difference": cents}}
+            There may be multiple valid maps if multiple changing pitches can be permuted.
+        """
+        # Find common pitches (same pitch class in both)
+        c1_collapsed = [p.collapse() for p in c1_pitches]
+        c2_collapsed = [p.collapse() for p in c2_transposed_pitches]
+
+        common_indices_c1 = []
+        common_indices_c2 = []
+        for i, pc1 in enumerate(c1_collapsed):
+            for j, pc2 in enumerate(c2_collapsed):
+                if pc1 == pc2:
+                    common_indices_c1.append(i)
+                    common_indices_c2.append(j)
+                    break
+
+        # Get changing pitch indices
+        changing_indices_c1 = [
+            i for i in range(len(c1_pitches)) if i not in common_indices_c1
+        ]
+        changing_indices_c2 = [
+            i for i in range(len(c2_transposed_pitches)) if i not in common_indices_c2
+        ]
+
+        # Build base map for common pitches (movement = 0 cents)
+        base_map = {}
+        for i in common_indices_c1:
+            p1 = c1_pitches[i]
+            p2 = c2_transposed_pitches[common_indices_c2[common_indices_c1.index(i)]]
+            base_map[p1] = {"destination": p2, "cent_difference": 0}
+
+        # If no changing pitches, return just the base map
+        if not changing_indices_c1:
+            return [base_map]
+
+        # For changing pitches, find all valid permutations
+        # Each changing pitch in c2 must be adjacent to some pitch in c1
+        c1_changing = [c1_pitches[i] for i in changing_indices_c1]
+        c2_changing = [c2_transposed_pitches[i] for i in changing_indices_c2]
+
+        # Find valid pairings: which c1 pitch can map to which c2 pitch (must be adjacent)
+        valid_pairings = []
+        for p1 in c1_changing:
+            pairings = []
+            for p2 in c2_changing:
+                if self._is_adjacent_pitches(p1, p2):
+                    cents = abs(p1.to_cents() - p2.to_cents())
+                    pairings.append((p1, p2, cents))
+            valid_pairings.append(pairings)
+
+        # Generate all permutations and filter valid ones
+        from itertools import permutations
+
+        all_maps = []
+        num_changing = len(c2_changing)
+
+        # For each permutation of c2_changing indices
+        for perm in permutations(range(num_changing)):
+            new_map = dict(base_map)  # Start with common pitches
+
+            valid = True
+            for i, c1_idx in enumerate(changing_indices_c1):
+                p1 = c1_pitches[c1_idx]
+                p2 = c2_changing[perm[i]]
+                cents = abs(p1.to_cents() - p2.to_cents())
+                new_map[p1] = {"destination": p2, "cent_difference": cents}
+
+            if valid:
+                all_maps.append(new_map)
+
+        return all_maps
+
     def _calc_symdiff_expanded(self, c1: Chord, c2: Chord) -> int:
         """Calculate symmetric difference on transposed (expanded) pitches.
 
@@ -512,29 +606,24 @@ class HarmonicSpace:
 
     def _check_melodic_threshold(
         self,
-        c1,
+        movements: dict,
-        c2,
         threshold_cents: float,
     ) -> bool:
-        """Check if pitch movements stay within melodic threshold."""
+        """Check if changing pitch movements stay within melodic threshold.
-        # Find common pitches (ignoring octaves)
-        c1_collapsed = [p.collapse() for p in c1]
-        c2_collapsed = [p.collapse() for p in c2]
 
-        common = set(c1_collapsed) & set(c2_collapsed)
+        Args:
+            movements: Dict mapping source pitch -> {destination, cent_difference}
+            threshold_cents: Maximum allowed movement in cents
 
-        if not common:
+        Returns:
-            return False
+            True if all movements are within threshold.
-
+            Common pitches (0 cents) always pass.
-        # Check movements from common pitches
+            Changing pitches must have cent_difference <= threshold.
-        for p1 in c1:
+        """
-            p1_c = p1.collapse()
+        for src, data in movements.items():
-            if p1_c in common:
+            cents = data["cent_difference"]
-                for p2 in c2:
+            # Common pitches have 0 cent difference - always pass
-                    p2_c = p2.collapse()
+            # Changing pitches: check if movement is within threshold
-                    if p1_c == p2_c:
-                        # Found matching pitch, check cent difference
-                        cents = abs(p1.to_cents() - p2.to_cents())
             if cents > threshold_cents:
                 return False
 
@@ -644,8 +733,8 @@ class PathFinder:
             "contrary_motion": True,
             "direct_tuning": True,
             "voice_crossing": True,
-            "sustained_voice": False,
+            "melodic_threshold_min": 0,
-            "transposition": False,
+            "melodic_threshold_max": 500,
         }
 
     def _calculate_edge_weights(
@@ -658,10 +747,41 @@ class PathFinder:
         """Calculate weights for edges based on configuration."""
         weights = []
 
+        # Get melodic threshold settings
+        melodic_min = config.get("melodic_threshold_min", 0)
+        melodic_max = config.get("melodic_threshold_max", float("inf"))
+
         for edge in out_edges:
             w = 1.0
             edge_data = edge[2]
 
+            # Get movements
+            movements = edge_data.get("movements", {})
+
+            # Melodic threshold check: ALL movements must be within min/max range (using absolute values)
+            if melodic_min is not None or melodic_max is not None:
+                cent_diffs = [
+                    abs(v.get("cent_difference", 0)) for v in movements.values()
+                ]
+
+                all_within_range = True
+                for cents in cent_diffs:
+                    if melodic_min is not None and cents < melodic_min:
+                        all_within_range = False
+                        break
+                    if melodic_max is not None and cents > melodic_max:
+                        all_within_range = False
+                        break
+
+                if all_within_range:
+                    w *= 10  # Boost for within range
+                else:
+                    w = 0.0  # Penalty for outside range
+
+                if w == 0.0:
+                    weights.append(w)
+                    continue
+
             # Movement size weight
             if config.get("movement_size", False):
                 movements = edge_data.get("movements", {})
@@ -777,6 +897,18 @@ def main():
         default=2,
         help="Maximum symmetric difference between chords",
     )
+    parser.add_argument(
+        "--melodic-min",
+        type=int,
+        default=0,
+        help="Minimum cents for any pitch movement (0 = no minimum)",
+    )
+    parser.add_argument(
+        "--melodic-max",
+        type=int,
+        default=500,
+        help="Maximum cents for any pitch movement (0 = no maximum)",
+    )
     parser.add_argument(
         "--dims", type=int, default=7, help="Number of prime dimensions (4, 5, 7, or 8)"
     )
@@ -815,7 +947,6 @@ def main():
         chords,
         symdiff_min=args.symdiff_min,
         symdiff_max=args.symdiff_max,
-        melodic_threshold_cents=200,
     )
     print(f"Graph: {graph.number_of_nodes()} nodes, {graph.number_of_edges()} edges")
 
@@ -823,7 +954,15 @@ def main():
     print("Finding stochastic path...")
     path_finder = PathFinder(graph)
     seed(args.seed)
-    path = path_finder.find_stochastic_path(max_length=args.max_path)
+
+    # Set up weights config with melodic thresholds
+    weights_config = path_finder._default_weights_config()
+    weights_config["melodic_threshold_min"] = args.melodic_min
+    weights_config["melodic_threshold_max"] = args.melodic_max
+
+    path = path_finder.find_stochastic_path(
+        max_length=args.max_path, weights_config=weights_config
+    )
     print(f"Path length: {len(path)}")
 
     # Write output