revert previous 2 and update test

Author: ethanglaser

faiss/svs/IndexSVSVamana.cpp

@@ -71,7 +71,6 @@ IndexSVSVamana::IndexSVSVamana(
           graph_max_degree{degree},
           is_static{is_static},
           storage_kind{storage} {
-    is_trained = false;
     prune_to = graph_max_degree < 4 ? graph_max_degree : graph_max_degree - 4;
     alpha = metric == METRIC_L2 ? 1.2f : 0.95f;
 
@@ -158,7 +157,6 @@ void IndexSVSVamana::add(idx_t n, const float* x) {
         std::memcpy(stored_vectors.data() + prev, x, sizeof(float) * n * d);
     }
     ntotal += n;
-    is_trained = true;
 }
 
 void IndexSVSVamana::reconstruct(idx_t key, float* recons) const {

tests/test_svs_py.py

@@ -1346,7 +1346,6 @@ def test_static_construction(self):
         """is_static is set on the constructed index"""
         index = self._create_static()
         self.assertTrue(index.is_static)
-        self.assertFalse(index.is_trained)
 
     def test_static_add_and_search(self):
         """add() builds the static index and search returns shaped output"""