[hist] Using explicit implementation of the THnSparse copy constructor

Author: Petr Jacka

hist/hist/inc/THnSparse.h

@@ -79,6 +79,8 @@ class THnSparse: public THnBase {
    THnSparse(const char *name, const char *title, Int_t dim, const Int_t *nbins,
        const std::vector<std::vector<double>> &xbins, Int_t chunksize = 1024 * 16);
 
+   THnSparse(const THnSparse& other);
+
    ~THnSparse() override;
 
    static THnSparse* CreateSparse(const char* name, const char* title,

hist/hist/src/THnSparse.cxx

@@ -644,6 +644,26 @@ THnBase(name, title, dim, nbins, xbins),
    fBinContent.SetOwner();
 }
 
+////////////////////////////////////////////////////////////////////////////////
+/// Construct a THnSparse as a copy of "other"
+
+THnSparse::THnSparse(const THnSparse& other):
+   THnBase(other), fChunkSize(other.fChunkSize), fFilledBins(other.fFilledBins),
+   fBinContent(other.fBinContent), fBins(other.fBins), fBinsContinued(other.fBinsContinued),
+   fCompactCoord(nullptr) {
+   
+   fBinContent.SetOwner();
+   
+   Int_t dim = other.GetNdimensions();
+   auto nbins=new Int_t[dim];
+   for (Int_t i=0; i<dim; i++)
+      nbins[i]=other.GetAxis(i)->GetNbins();
+   
+   fCompactCoord = new THnSparseCompactBinCoord(dim, nbins);
+   delete[] nbins;
+}
+
+
 ////////////////////////////////////////////////////////////////////////////////
 /// Destruct a THnSparse
 

hist/hist/test/THn.cxx

@@ -29,13 +29,15 @@ TEST(THn, Constructors) {
    THnD hn_v2("hn_v2", "hn_v2", 3, nbins.data(), edges);
    THnD hn_v3("hn_v3", "hn_v3", axes);
    THnI hn_v4("hn_v4", "hn_v4", axes);
+   THnD hn_v5(hn_v1);
 
    THnSparseD hs_v1("hs_v1", "hs_v1", 3, nbins.data(), xmin.data(), xmax.data());
    THnSparseD hs_v2("hs_v2", "hs_v2", 3, nbins.data(), edges);
    THnSparseD hs_v3("hs_v3", "hs_v3", axes);
    THnSparseI hs_v4("hs_v4", "hs_v4", axes);
+   THnSparseD hs_v5(hs_v1);
 
-   std::vector<THnBase*> hns = {&hn_v1, &hn_v2, &hn_v3, &hn_v4, &hs_v1, &hs_v2, &hs_v3, &hs_v4};
+   std::vector<THnBase*> hns = {&hn_v1, &hn_v2, &hn_v3, &hn_v4, &hn_v5, &hs_v1, &hs_v2, &hs_v3, &hs_v4, &hs_v5};
    for (THnBase* hn : hns) {
       EXPECT_EQ(hn->GetNdimensions(), 3);
       for (int dim = 0; dim < 3; ++dim) {