quantile

Signed-off-by: Mohit Chhaya <[email protected]>

Author: mrchhaya

cpp/csp/cppnodes/statsimpl.h

@@ -12,6 +12,10 @@
 #ifdef __linux__
 #include <ext/pb_ds/assoc_container.hpp>
 #include <ext/pb_ds/tree_policy.hpp>
+#else
+#include <boost/multi_index_container.hpp>
+#include <boost/multi_index/ordered_index.hpp>
+#include <boost/multi_index/ranked_index.hpp>
 #endif
 
 namespace csp::cppnodes
@@ -1099,6 +1103,9 @@ void ost_erase( ost<Comparator> &t, double & v )
     auto it = t.find_by_order( rank );
     t.erase( it );
 }
+#else
+template <typename Comparator>
+using ost = boost::multi_index::multi_index_container<double, boost::multi_index::indexed_by<boost::multi_index::ranked_non_unique<boost::multi_index::identity<double>, Comparator>>>;
 #endif
 
 class Quantile
@@ -1214,52 +1221,50 @@ class Quantile
                     break;
             }
         #else
-            auto it = m_tree.begin();
-            std::advance( it, ft );
-            switch ( m_interpolation )
+            switch (m_interpolation)
             {
-                case LINEAR:
-                    if( ft == target )
-                    {
-                        qtl = *it;
-                    }
-                    else
-                    {
-                        double lower = *it;
-                        double higher = *++it;
-                        qtl = ( 1 - target + ft ) * lower + ( 1 - ct + target ) * higher;
-                    }
-                    break;
-                case LOWER:
-                    qtl = *it;
-                    break;
-                case HIGHER:
-                    qtl = ( ft == ct ? *it : *++it );
-                    break;
-                case MIDPOINT:
-                    if( ft == target )
-                    {
-                        qtl = *it;
-                    }
-                    else
-                    {
-                        double lower = *it;
-                        double higher = *++it;
-                        qtl = ( higher+lower ) / 2;
-                    }
-                    break;
-                case NEAREST:
-                    if( target - ft <= ct - target )
-                    {
-                        qtl = *it;
-                    }
-                    else
-                    {
-                        qtl = *++it;
-                    }
-                    break;
-                default:
-                    break;
+            case LINEAR:
+                if (ft == target)
+                {
+                    qtl = *m_tree.get<0>().nth(ft);
+                }
+                else
+                {
+                    double lower = *m_tree.get<0>().nth(ft);
+                    double higher = *m_tree.get<0>().nth(ct);
+                    qtl = (1 - target + ft) * lower + (1 - ct + target) * higher;
+                }
+                break;
+            case LOWER:
+                qtl = *m_tree.get<0>().nth(ft);
+                break;
+            case HIGHER:
+                qtl = *m_tree.get<0>().nth(ct);
+                break;
+            case MIDPOINT:
+                if (ft == target)
+                {
+                    qtl = *m_tree.get<0>().nth(ft);
+                }
+                else
+                {
+                    double lower = *m_tree.get<0>().nth(ft);
+                    double higher = *m_tree.get<0>().nth(ct);
+                    qtl = (higher + lower) / 2;
+                }
+                break;
+            case NEAREST:
+                if (target - ft < ct - target)
+                {
+                    qtl = *m_tree.get<0>().nth(ft);
+                }
+                else
+                {
+                    qtl = *m_tree.get<0>().nth(ct);
+                }
+                break;
+            default:
+                break;
             }
         #endif
             return qtl;
@@ -1270,7 +1275,7 @@ class Quantile
     #ifdef __linux__
         ost<std::less_equal<double>> m_tree;
     #else
-        std::multiset<double> m_tree;
+        ost<std::less<double>> m_tree;
     #endif
         std::vector<Dictionary::Data> m_quants;
         int64_t m_interpolation;