Remove mode parameter, always use STRONG configuration

schulzchristian · claude · schulzchristian · commit 511a99646bc4 · 2026-02-10T09:56:06.000+01:00
Co-Authored-By: Claude Opus 4.6 &lt;noreply@anthropic.com&gt;
diff --git a/README.md b/README.md
@@ -86,7 +86,7 @@ g.add_undirected_edge(2, 3, 1)  # weak bridge between two communities
 # Convert to CSR format and cluster
 vwgt, xadj, adjcwgt, adjncy = g.get_csr_arrays()
 modularity, clustering = vieclus.cluster(vwgt, xadj, adjcwgt, adjncy,
-                                         mode=vieclus.STRONG, time_limit=1.0)
+                                         time_limit=1.0)
 
 print(f"Modularity: {modularity}")
 print(f"Clustering: {clustering}")
@@ -106,7 +106,6 @@ adjcwgt = [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1]
 modularity, clustering = vieclus.cluster(vwgt, xadj, adjcwgt, adjncy,
                                          suppress_output=True,
                                          seed=0,
-                                         mode=vieclus.ECO,
                                          time_limit=2.0)
 
 print(f"Modularity: {modularity}")
@@ -125,7 +124,6 @@ The `vieclus.cluster` function takes the following arguments:
 | `adjncy` | list | *required* | CSR adjacency array (length m) |
 | `suppress_output` | bool | `True` | Suppress console output |
 | `seed` | int | `0` | Random seed |
-| `mode` | int | `STRONG` | Clustering mode: `vieclus.FAST`, `vieclus.ECO`, or `vieclus.STRONG` |
 | `time_limit` | float | `1.0` | Time limit in seconds |
 | `cluster_upperbound` | int | `0` | Max cluster size (0 = no limit) |
 
@@ -137,7 +135,7 @@ Release Notes
 ### v1.2
 - Added Python interface (`pip install vieclus`) with pybind11 bindings
 - Added `vieclus_graph` helper class for easy graph construction (same interface as KaHIP)
-- Added `vieclus.cluster()` function with FAST, ECO, and STRONG modes
+- Added `vieclus.cluster()` function
 - Added PyPI packaging with scikit-build-core
 - Added GitHub Actions CI and automated PyPI publishing
 - Added NOMPI compilation support
diff --git a/interface/vieclus_interface.cpp b/interface/vieclus_interface.cpp
@@ -27,25 +27,6 @@
 #include <omp.h>
 #endif
 
-static void internal_vieclus_set_configuration(configuration & cfg,
-                                               PartitionConfig & config,
-                                               int mode) {
-        switch (mode) {
-                case VIECLUS_FAST:
-                        cfg.fast(config);
-                        break;
-                case VIECLUS_ECO:
-                        cfg.eco(config);
-                        break;
-                case VIECLUS_STRONG:
-                        cfg.strong(config);
-                        break;
-                default:
-                        cfg.eco(config);
-                        break;
-        }
-}
-
 static void internal_build_graph(int* n,
                                  int* vwgt,
                                  int* xadj,
@@ -69,7 +50,7 @@ static void internal_build_graph(int* n,
 
 void vieclus_clustering(int* n, int* vwgt, int* xadj,
                         int* adjcwgt, int* adjncy,
-                        bool suppress_output, int seed, int mode,
+                        bool suppress_output, int seed,
                         double time_limit, int cluster_upperbound,
                         double* modularity, int* num_clusters, int* clustering) {
 
@@ -81,10 +62,10 @@ void vieclus_clustering(int* n, int* vwgt, int* xadj,
         omp_set_num_threads(1);
 #endif
 
-        // Configure
+        // Configure (always use STRONG)
         PartitionConfig config;
         configuration cfg;
-        internal_vieclus_set_configuration(cfg, config, mode);
+        cfg.strong(config);
 
         config.k = 1;
         config.seed = seed;
diff --git a/interface/vieclus_interface.h b/interface/vieclus_interface.h
@@ -12,11 +12,7 @@ extern "C"
 {
 #endif
 
-const int VIECLUS_FAST   = 0;
-const int VIECLUS_ECO    = 1;
-const int VIECLUS_STRONG = 2;
-
-// Graph clustering using VieClus.
+// Graph clustering using VieClus (always uses STRONG configuration).
 // Uses METIS CSR format (same as KaHIP).
 //
 // Input:
@@ -27,7 +23,6 @@ const int VIECLUS_STRONG = 2;
 //   adjncy        - CSR adjacency array (array of m ints)
 //   suppress_output - if true, suppress console output
 //   seed          - random seed
-//   mode          - VIECLUS_FAST (0), VIECLUS_ECO (1), or VIECLUS_STRONG (2)
 //   time_limit    - time limit in seconds
 //   cluster_upperbound - max cluster size (0 = no limit)
 //
@@ -37,7 +32,7 @@ const int VIECLUS_STRONG = 2;
 //   clustering    - cluster assignment array (array of n ints, must be pre-allocated)
 void vieclus_clustering(int* n, int* vwgt, int* xadj,
                         int* adjcwgt, int* adjncy,
-                        bool suppress_output, int seed, int mode,
+                        bool suppress_output, int seed,
                         double time_limit, int cluster_upperbound,
                         double* modularity, int* num_clusters, int* clustering);
 
diff --git a/misc/pymodule/vieclus.cpp b/misc/pymodule/vieclus.cpp
@@ -14,7 +14,6 @@ pybind11::object wrap_vieclus(
                 const pybind11::object &adjncy,
                 bool suppress_output,
                 int seed,
-                int mode,
                 double time_limit,
                 int cluster_upperbound) {
         int n = pybind11::len(xadj) - 1;
@@ -38,7 +37,7 @@ pybind11::object wrap_vieclus(
 
         vieclus_clustering(&n, &vwgtv[0], &xadjv[0],
                            &adjwgtv[0], &adjncyv[0],
-                           suppress_output, seed, mode,
+                           suppress_output, seed,
                            time_limit, cluster_upperbound,
                            &modularity, &num_clusters, clustering);
 
@@ -60,7 +59,6 @@ PYBIND11_MODULE(vieclus, m) {
               pybind11::arg("adjncy"),
               pybind11::arg("suppress_output") = true,
               pybind11::arg("seed") = 0,
-              pybind11::arg("mode") = 2,
               pybind11::arg("time_limit") = 1.0,
               pybind11::arg("cluster_upperbound") = 0);
 }
diff --git a/python/vieclus/__init__.py b/python/vieclus/__init__.py
@@ -17,12 +17,6 @@
         "Make sure the package is properly installed."
     ) from e
 
-# Clustering mode constants
-FAST = 0
-ECO = 1
-STRONG = 2
-
-
 class vieclus_graph:
     """Graph class for constructing graphs and converting to CSR format for VieClus.
 
@@ -87,4 +81,4 @@ def get_csr_arrays(self):
         return vwgt, xadj, adjcwgt, adjncy
 
 
-__all__ = ["cluster", "vieclus_graph", "__version__", "FAST", "ECO", "STRONG"]
+__all__ = ["cluster", "vieclus_graph", "__version__"]
diff --git a/test_vieclus.py b/test_vieclus.py
@@ -3,7 +3,6 @@
 
 print("=== Test 1: Import and version ===")
 print(f"VieClus version: {vieclus.__version__}")
-print(f"Mode constants: FAST={vieclus.FAST}, ECO={vieclus.ECO}, STRONG={vieclus.STRONG}")
 
 print("\n=== Test 2: vieclus_graph helper class ===")
 # Build a small graph with two clear communities:
@@ -31,12 +30,11 @@
 print(f"  num nodes: {g.num_nodes}")
 print(f"  num edges (directed): {len(adjncy)}")
 
-print("\n=== Test 3: Clustering with FAST mode ===")
+print("\n=== Test 3: Clustering (two communities) ===")
 modularity, clustering = vieclus.cluster(
     vwgt, xadj, adjcwgt, adjncy,
     suppress_output=False,
     seed=0,
-    mode=vieclus.FAST,
     time_limit=1.0
 )
 print(f"  Modularity: {modularity:.6f}")
@@ -47,12 +45,11 @@
 assert modularity > 0, f"Expected positive modularity, got {modularity}"
 print("  PASSED")
 
-print("\n=== Test 4: Clustering with ECO mode ===")
+print("\n=== Test 4: Clustering with different seed ===")
 modularity, clustering = vieclus.cluster(
     vwgt, xadj, adjcwgt, adjncy,
     suppress_output=True,
     seed=42,
-    mode=vieclus.ECO,
     time_limit=1.0
 )
 print(f"  Modularity: {modularity:.6f}")
@@ -63,23 +60,7 @@
 assert modularity > 0
 print("  PASSED")
 
-print("\n=== Test 5: Clustering with STRONG mode ===")
-modularity, clustering = vieclus.cluster(
-    vwgt, xadj, adjcwgt, adjncy,
-    suppress_output=True,
-    seed=0,
-    mode=vieclus.STRONG,
-    time_limit=1.0
-)
-print(f"  Modularity: {modularity:.6f}")
-print(f"  Clustering: {list(clustering)}")
-num_clusters = len(set(clustering))
-print(f"  Number of clusters: {num_clusters}")
-assert len(clustering) == 6
-assert modularity > 0
-print("  PASSED")
-
-print("\n=== Test 6: Raw CSR arrays (5-node path graph) ===")
+print("\n=== Test 5: Raw CSR arrays (5-node path graph) ===")
 # Simple path: 0-1-2-3-4
 xadj   = [0, 1, 3, 5, 7, 8]
 adjncy = [1, 0, 2, 1, 3, 2, 4, 3]
@@ -90,7 +71,6 @@
     vwgt, xadj, adjcwgt, adjncy,
     suppress_output=True,
     seed=0,
-    mode=vieclus.ECO,
     time_limit=1.0
 )
 print(f"  Modularity: {modularity:.6f}")
