From c4fb76429909feef526f6d5d72463595b5462547 Mon Sep 17 00:00:00 2001
From: Frank Dellaert <dellaert@gmail.com>
Date: Sat, 7 Jan 2023 10:19:52 -0800
Subject: [PATCH] Removed boost headers in DecisionTree-inl.h that are no
 longer needed.

---
 gtsam/discrete/DecisionTree-inl.h            | 11 ++---------
 gtsam_unstable/discrete/Domain.cpp           |  3 +--
 gtsam_unstable/discrete/SingleValue.cpp      |  3 +--
 gtsam_unstable/discrete/tests/testSudoku.cpp |  6 +++---
 4 files changed, 7 insertions(+), 16 deletions(-)

diff --git a/gtsam/discrete/DecisionTree-inl.h b/gtsam/discrete/DecisionTree-inl.h
index d01c91840..9f3d5e8f9 100644
--- a/gtsam/discrete/DecisionTree-inl.h
+++ b/gtsam/discrete/DecisionTree-inl.h
@@ -22,14 +22,10 @@
 #include <gtsam/discrete/DecisionTree.h>
 
 #include <algorithm>
-#include <boost/assign/std/vector.hpp>
 #include <boost/format.hpp>
 #include <boost/make_shared.hpp>
-#include <boost/noncopyable.hpp>
 #include <boost/optional.hpp>
-#include <boost/tuple/tuple.hpp>
-#include <boost/type_traits/has_dereference.hpp>
-#include <boost/unordered_set.hpp>
+
 #include <cmath>
 #include <fstream>
 #include <list>
@@ -41,8 +37,6 @@
 
 namespace gtsam {
 
-  using boost::assign::operator+=;
-
   /****************************************************************************/
   // Node
   /****************************************************************************/
@@ -535,8 +529,7 @@ namespace gtsam {
   template<typename L, typename Y>
   DecisionTree<L, Y>::DecisionTree(const L& label,
       const DecisionTree& f0, const DecisionTree& f1)  {
-    std::vector<DecisionTree> functions;
-    functions += f0, f1;
+    const std::vector<DecisionTree> functions{f0, f1};
     root_ = compose(functions.begin(), functions.end(), label);
   }
 
diff --git a/gtsam_unstable/discrete/Domain.cpp b/gtsam_unstable/discrete/Domain.cpp
index 7acc10cb4..cf0da42e7 100644
--- a/gtsam_unstable/discrete/Domain.cpp
+++ b/gtsam_unstable/discrete/Domain.cpp
@@ -37,8 +37,7 @@ double Domain::operator()(const DiscreteValues& values) const {
 
 /* ************************************************************************* */
 DecisionTreeFactor Domain::toDecisionTreeFactor() const {
-  DiscreteKeys keys;
-  keys += DiscreteKey(key(), cardinality_);
+  const DiscreteKeys keys{DiscreteKey(key(), cardinality_)};
   vector<double> table;
   for (size_t i1 = 0; i1 < cardinality_; ++i1) table.push_back(contains(i1));
   DecisionTreeFactor converted(keys, table);
diff --git a/gtsam_unstable/discrete/SingleValue.cpp b/gtsam_unstable/discrete/SingleValue.cpp
index 6dd81a7dc..fc5fab83f 100644
--- a/gtsam_unstable/discrete/SingleValue.cpp
+++ b/gtsam_unstable/discrete/SingleValue.cpp
@@ -29,8 +29,7 @@ double SingleValue::operator()(const DiscreteValues& values) const {
 
 /* ************************************************************************* */
 DecisionTreeFactor SingleValue::toDecisionTreeFactor() const {
-  DiscreteKeys keys;
-  keys += DiscreteKey(keys_[0], cardinality_);
+  const DiscreteKeys keys{DiscreteKey(keys_[0], cardinality_)};
   vector<double> table;
   for (size_t i1 = 0; i1 < cardinality_; i1++) table.push_back(i1 == value_);
   DecisionTreeFactor converted(keys, table);
diff --git a/gtsam_unstable/discrete/tests/testSudoku.cpp b/gtsam_unstable/discrete/tests/testSudoku.cpp
index 9796c25f1..a47611222 100644
--- a/gtsam_unstable/discrete/tests/testSudoku.cpp
+++ b/gtsam_unstable/discrete/tests/testSudoku.cpp
@@ -58,14 +58,14 @@ class Sudoku : public CSP {
     // add row constraints
     for (size_t i = 0; i < n; i++) {
       DiscreteKeys dkeys;
-      for (size_t j = 0; j < n; j++) dkeys += dkey(i, j);
+      for (size_t j = 0; j < n; j++) dkeys.push_back(dkey(i, j));
       addAllDiff(dkeys);
     }
 
     // add col constraints
     for (size_t j = 0; j < n; j++) {
       DiscreteKeys dkeys;
-      for (size_t i = 0; i < n; i++) dkeys += dkey(i, j);
+      for (size_t i = 0; i < n; i++) dkeys.push_back(dkey(i, j));
       addAllDiff(dkeys);
     }
 
@@ -77,7 +77,7 @@ class Sudoku : public CSP {
         // Box I,J
         DiscreteKeys dkeys;
         for (size_t i = i0; i < i0 + N; i++)
-          for (size_t j = j0; j < j0 + N; j++) dkeys += dkey(i, j);
+          for (size_t j = j0; j < j0 + N; j++) dkeys.push_back(dkey(i, j));
         addAllDiff(dkeys);
         j0 += N;
       }