1 files changed, 48 insertions, 0 deletions
diff --git a/lib/include/wolff/models/dihedral.hpp b/lib/include/wolff/models/dihedral.hpp
new file mode 100644
index 0000000..cbc5687
--- /dev/null
+++ b/lib/include/wolff/models/dihedral.hpp
@@ -0,0 +1,48 @@
+
+#pragma once
+
+#include <wolff/types.h>
+#include "potts.hpp"
+
+template <q_t q>
+class dihedral_t {
+  public:
+    bool is_reflection;
+    q_t x;
+
+    dihedral_t() : is_reflection(false), x(0) {}
+    dihedral_t(bool x, q_t y) : is_reflection(x), x(y) {}
+
+    potts_t<q> act(const potts_t<q>& s) const {
+      if (this->is_reflection) {
+        return potts_t<q>(((q + this->x) - s.x) % q);
+      } else {
+        return potts_t<q>((this->x + s.x) % q);
+      }
+    }
+
+    dihedral_t<q> act(dihedral_t<q> r) const {
+      if (this->is_reflection) {
+        return dihedral_t<q>(!(r.is_reflection), ((q + this->x) - r.x) % q); 
+      } else {
+        return dihedral_t<q>(r.is_reflection, (this->x + r.x) % q);
+      }
+    }
+
+    potts_t<q> act_inverse(potts_t<q> s) const {
+      if (this->is_reflection) {
+        return this->act(s);
+      } else {
+        return potts_t<q>(((s.x + q) - this->x) % q);
+      }
+    }
+
+    dihedral_t<q> act_inverse(dihedral_t<q> r) const {
+      if (this->is_reflection) {
+        return this->act(r);
+      } else {
+        return dihedral_t<q>(r.is_reflection, ((r.x + q) - this->x) % q);
+      }
+    }
+};
+