Rename: explain -> superposition

src/math/polysat/superposition.h

@@ -0,0 +1,38 @@
+/*++
+Copyright (c) 2021 Microsoft Corporation
+
+Module Name:
+
+    Conflict explanation by polynomial superposition
+
+Author:
+
+    Nikolaj Bjorner (nbjorner) 2021-03-19
+    Jakob Rath 2021-04-06
+
+--*/
+#pragma once
+#include "math/polysat/conflict.h"
+#include "math/polysat/constraint.h"
+#include "math/polysat/clause_builder.h"
+#include "math/polysat/interval.h"
+
+namespace polysat {
+
+    class solver;
+
+    class ex_polynomial_superposition {
+        solver& s;
+
+        signed_constraint resolve1(pvar v, signed_constraint c1, signed_constraint c2);
+        lbool find_replacement(signed_constraint c2, pvar v, conflict& core);
+        void reduce_by(pvar v, conflict& core);
+        bool reduce_by(pvar, signed_constraint c, conflict& core);
+        lbool try_explain1(pvar v, conflict& core);
+
+    public:
+        ex_polynomial_superposition(solver& s) : s(s) {}
+        bool perform(pvar v, conflict& core);
+    };
+
+}