Ignore self-cycles in the condensation graph

Author: YingboMa

src/bipartite_graph.jl

@@ -589,10 +589,10 @@ end
 
 
 Graphs.outneighbors(mcg::MatchedCondensationGraph, cc::Integer) =
-    Iterators.flatten((mcg.scc_assignment[v′] for v′ in outneighbors(mcg.graph, v)) for v in mcg.sccs[cc])
+    Iterators.flatten((mcg.scc_assignment[v′] for v′ in outneighbors(mcg.graph, v) if mcg.scc_assignment[v′] != cc) for v in mcg.sccs[cc])
 
 Graphs.inneighbors(mcg::MatchedCondensationGraph, cc::Integer) =
-    Iterators.flatten((mcg.scc_assignment[v′] for v′ in inneighbors(mcg.graph, v)) for v in mcg.sccs[cc])
+    Iterators.flatten((mcg.scc_assignment[v′] for v′ in inneighbors(mcg.graph, v) if mcg.scc_assignment[v′] != cc) for v in mcg.sccs[cc])
 
 """
     struct InducedCondensationGraph

src/structural_transformation/codegen.jl

@@ -174,8 +174,9 @@ function build_torn_function(
     state = TearingState(sys)
     fullvars = state.fullvars
     var_eq_matching, var_sccs = algebraic_variables_scc(state)
-    toporder = reverse(topological_sort_by_dfs(MatchedCondensationGraph(
-        DiCMOBiGraph{true}(complete(state.structure.graph), complete(var_eq_matching)), var_sccs)))
+    condensed_graph = MatchedCondensationGraph(
+        DiCMOBiGraph{true}(complete(state.structure.graph), complete(var_eq_matching)), var_sccs)
+    toporder = topological_sort_by_dfs(condensed_graph)
     var_sccs = var_sccs[toporder]
 
     states = map(i->fullvars[i], diffvars_range(state.structure))