Using C++23 to reimplement sort by using zip

hosseinmoein · Nov 24, 2023 · a08bd0c · a08bd0c
1 parent 6e382c3
commit a08bd0c
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Showing 8 changed files with 320 additions and 260 deletions.
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -34,7 +34,7 @@ add_library(DataFrame::DataFrame ALIAS DataFrame)
 
 target_sources(DataFrame PRIVATE src/Utils/DateTime.cc)
 
-target_compile_features(DataFrame PUBLIC cxx_std_20)
+target_compile_features(DataFrame PUBLIC cxx_std_23)
 target_compile_definitions(
     DataFrame
     PRIVATE $<$<BOOL:${HMDF_HAVE_CLOCK_GETTIME}>:HMDF_HAVE_CLOCK_GETTIME>

diff --git a/include/DataFrame/DataFrameTypes.h b/include/DataFrame/DataFrameTypes.h
@@ -579,10 +579,10 @@ struct  RandGenParams  {
     std::size_t     t_dist { 1 };
     // The μ distribution parameter (the mean of the distribution)
     //
-    double          mean { 1.0 };
+    double          mean { 0 };
     // the σ distribution parameter (standard deviation)
     //
-    double          std { 0 };
+    double          std { 1 };
     // The λ distribution parameter (the rate parameter)
     //
     double          lambda { 1.0 };

diff --git a/include/DataFrame/Internals/DataFrame.tcc b/include/DataFrame/Internals/DataFrame.tcc
diff --git a/include/DataFrame/Internals/DataFrame_functors.h b/include/DataFrame/Internals/DataFrame_functors.h
@@ -67,8 +67,7 @@ struct sort_functor_ : DataVec::template visitor_base<Ts ...>  {
         : sorted_idxs(si), idx_s(is)  {   }
 
     const StlVecType<size_t>   &sorted_idxs;
-    StlVecType<size_t>         sorted_idxs_copy;
-    const size_t                idx_s;
+    const size_t               idx_s;
 
     template<typename T2>
     void operator() (T2 &vec);

diff --git a/include/DataFrame/Internals/DataFrame_misc.tcc b/include/DataFrame/Internals/DataFrame_misc.tcc
@@ -77,8 +77,7 @@ template<typename T2>
 void
 DataFrame<I, H>::sort_functor_<Ts ...>::operator() (T2 &vec)  {
 
-    sorted_idxs_copy = sorted_idxs;
-    _sort_by_sorted_index_(vec, sorted_idxs_copy, idx_s);
+    _sort_by_sorted_index_(vec, sorted_idxs, idx_s);
     return;
 }
 

diff --git a/include/DataFrame/Internals/DataFrame_standalone.tcc b/include/DataFrame/Internals/DataFrame_standalone.tcc
@@ -865,23 +865,24 @@ inline static O _remove_copy_if_(I first, I last, O d_first, PRE predicate)  {
 
 template<typename T, typename V>
 static inline void
-_sort_by_sorted_index_(T &to_be_sorted, V &sorting_idxs, size_t idx_s)  {
-
-    if (idx_s > 0)  {
-        idx_s -= 1;
-        for (size_t i = 0; i < idx_s; ++i) [[likely]]  {
-            // while the element i is not yet in place
-            //
-            while (sorting_idxs[i] != sorting_idxs[sorting_idxs[i]])  {
-                // swap it with the element at its final place
-                //
-                const size_t    j = sorting_idxs[i];
-
-                std::swap(to_be_sorted[j], to_be_sorted[sorting_idxs[j]]);
-                std::swap(sorting_idxs[i], sorting_idxs[j]);
+_sort_by_sorted_index_(T &to_be_sorted, const V &sorting_idxs, size_t idx_s) {
+
+    std::vector<bool>   done (idx_s, false);
+
+    for (std::size_t i = 0; i < idx_s; ++i) [[likely]]
+        if (! done[i])  {
+            done[i] = true;
+
+            std::size_t prev_j = i;
+            std::size_t j = sorting_idxs[i];
+
+            while (i != j)  {
+                std::swap(to_be_sorted[prev_j], to_be_sorted[j]);
+                done[j] = true;
+                prev_j = j;
+                j = sorting_idxs[j];
             }
         }
-    }
 }
 
 // ----------------------------------------------------------------------------

diff --git a/src/Makefile.Linux.GCC64 b/src/Makefile.Linux.GCC64
@@ -11,7 +11,7 @@ CXX = /usr/bin/g++
 INCLUDES = -I/usr/include/c++/7 -I/usr/include
 
 LFLAGS =
-CXXFLAGS = -O3 $(INCLUDES) $(DEFINES) -std=c++20
+CXXFLAGS = -O3 $(INCLUDES) $(DEFINES) -std=c++2b
 
 PLATFORM_LIBS = -lpthread -ldl -lm -lstdc++
 

diff --git a/src/Makefile.Linux.GCC64D b/src/Makefile.Linux.GCC64D
@@ -11,8 +11,8 @@ CXX = /usr/bin/g++
 INCLUDES = -I/usr/include/c++/7 -I/usr/inc17lude
 
 LFLAGS =
-CXXFLAGS = -g $(INCLUDES) $(DEFINES) -D_GLIBCXX_DEBUG -pedantic -Wall -Wextra -std=c++20
-# CXXFLAGS = -g $(INCLUDES) $(DEFINES) -std=c++20
+CXXFLAGS = -g $(INCLUDES) $(DEFINES) -D_GLIBCXX_DEBUG -pedantic -Wall -Wextra -std=c++2b
+# CXXFLAGS = -g $(INCLUDES) $(DEFINES) -std=c++2b
 
 PLATFORM_LIBS = -lpthread -ldl -lm -lstdc++ -fsanitize-address-use-after-scope -fsanitize=address