put Ring struct in a separate file

gtsam/discrete/AlgebraicDecisionTree.h

@@ -20,12 +20,12 @@
 
 #include <gtsam/base/Testable.h>
 #include <gtsam/discrete/DecisionTree-inl.h>
+#include <gtsam/discrete/Ring.h>
 
-#include <algorithm>
+#include <iomanip>
 #include <limits>
 #include <map>
 #include <string>
-#include <iomanip>
 #include <vector>
 
 namespace gtsam {
@@ -55,26 +55,6 @@ namespace gtsam {
    public:
     using Base = DecisionTree<L, double>;
 
-    /** The Real ring with addition and multiplication */
-    struct Ring {
-      static inline double zero() { return 0.0; }
-      static inline double one() { return 1.0; }
-      static inline double add(const double& a, const double& b) {
-        return a + b;
-      }
-      static inline double max(const double& a, const double& b) {
-        return std::max(a, b);
-      }
-      static inline double mul(const double& a, const double& b) {
-        return a * b;
-      }
-      static inline double div(const double& a, const double& b) {
-        return a / b;
-      }
-      static inline double id(const double& x) { return x; }
-      static inline double negate(const double& x) { return -x; }
-    };
-
     AlgebraicDecisionTree(double leaf = 1.0) : Base(leaf) {}
 
     // Explicitly non-explicit constructor

gtsam/discrete/DiscreteConditional.cpp

@@ -19,6 +19,7 @@
 #include <gtsam/base/Testable.h>
 #include <gtsam/base/debug.h>
 #include <gtsam/discrete/DiscreteConditional.h>
+#include <gtsam/discrete/Ring.h>
 #include <gtsam/discrete/Signature.h>
 #include <gtsam/hybrid/HybridValues.h>
 
@@ -104,7 +105,7 @@ DiscreteConditional DiscreteConditional::operator*(
   // Finally, add parents to keys, in order
   for (auto&& dk : parents) discreteKeys.push_back(dk);
 
-  ADT product = ADT::apply(other, ADT::Ring::mul);
+  ADT product = ADT::apply(other, Ring::mul);
   return DiscreteConditional(newFrontals.size(), discreteKeys, product);
 }
 

gtsam/discrete/Ring.h

@@ -0,0 +1,37 @@
+/* ----------------------------------------------------------------------------
+
+ * GTSAM Copyright 2010, Georgia Tech Research Corporation,
+ * Atlanta, Georgia 30332-0415
+ * All Rights Reserved
+ * Authors: Frank Dellaert, et al. (see THANKS for the full author list)
+
+ * See LICENSE for the license information
+
+ * -------------------------------------------------------------------------- */
+
+/**
+ * @file    Ring.h
+ * @brief   Real Ring definition
+ * @author  Varun Agrawal
+ * @date    Dec 8, 2024
+ */
+
+#pragma once
+
+#include <algorithm>
+
+/** The Real ring with addition and multiplication */
+struct Ring {
+  static inline double zero() { return 0.0; }
+  static inline double one() { return 1.0; }
+  static inline double add(const double& a, const double& b) { return a + b; }
+  static inline double max(const double& a, const double& b) {
+    return std::max(a, b);
+  }
+  static inline double mul(const double& a, const double& b) { return a * b; }
+  static inline double div(const double& a, const double& b) {
+    return (a == 0 || b == 0) ? 0 : (a / b);
+  }
+  static inline double id(const double& x) { return x; }
+  static inline double negate(const double& x) { return -x; }
+};

gtsam/discrete/TableFactor.h

@@ -19,6 +19,7 @@
 
 #include <gtsam/discrete/DiscreteFactor.h>
 #include <gtsam/discrete/DiscreteKey.h>
+#include <gtsam/discrete/Ring.h>
 #include <gtsam/inference/Ordering.h>
 
 #include <Eigen/Sparse>
@@ -99,21 +100,6 @@ class GTSAM_EXPORT TableFactor : public DiscreteFactor {
   using Binary = std::function<double(const double, const double)>;
 
  public:
-  /** The Real ring with addition and multiplication */
-  struct Ring {
-    static inline double zero() { return 0.0; }
-    static inline double one() { return 1.0; }
-    static inline double add(const double& a, const double& b) { return a + b; }
-    static inline double max(const double& a, const double& b) {
-      return std::max(a, b);
-    }
-    static inline double mul(const double& a, const double& b) { return a * b; }
-    static inline double div(const double& a, const double& b) {
-      return (a == 0 || b == 0) ? 0 : (a / b);
-    }
-    static inline double id(const double& x) { return x; }
-  };
-
   /// @name Standard Constructors
   /// @{
 

gtsam/discrete/tests/testDecisionTree.cpp

@@ -23,6 +23,7 @@
 #include <gtsam/base/Testable.h>
 #include <gtsam/base/serializationTestHelpers.h>
 #include <gtsam/discrete/DecisionTree-inl.h>
+#include <gtsam/discrete/Ring.h>
 #include <gtsam/discrete/Signature.h>
 #include <gtsam/inference/Symbol.h>
 
@@ -124,14 +125,6 @@ struct traits<DT> : public Testable<DT> {};
 
 GTSAM_CONCEPT_TESTABLE_INST(DT)
 
-struct Ring {
-  static inline int zero() { return 0; }
-  static inline int one() { return 1; }
-  static inline int id(const int& a) { return a; }
-  static inline int add(const int& a, const int& b) { return a + b; }
-  static inline int mul(const int& a, const int& b) { return a * b; }
-};
-
 /* ************************************************************************** */
 // Check that creating decision trees respects key order.
 TEST(DecisionTree, ConstructorOrder) {