Sanity check for Vary is too restrictive

[vepadulano]

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Description

One of the sanity checks done when calling the Vary operation is to make sure all columns to be varied are of the same type. This is done by string comparison, which is limiting because sometimes the same type might be hidden by a typedef. For a full description of the issue, see https://root-forum.cern.ch/t/inconsistent-behaviour-of-rdataframe-columntypes/62605

Reproducer

Reproducer from the forum issue

#include <ROOT/RDataFrame.hxx>
#include <ROOT/RVec.hxx>
#include <TFile.h>
#include <TTree.h>

int create_root_file()
{
        TFile* f = TFile::Open("tree.root", "RECREATE");
        TTree *t = new TTree("tree", "tree");
        Float_t v[3] = {0., 1., 2.};
        t->Branch("v", &v, "v[3]/F");
        t->Branch("w", &v, "w[3]/F");
        t->Fill();
        t->Write();
        f->Close();
        return 0;
}


int main()
{
        create_root_file();

        ROOT::RDataFrame df_start("tree", "tree.root");
        auto df = df_start.Filter("true");
        auto t1 = df.GetColumnType("v");
        df = df.Redefine("v", "v");
        auto t2 = df.GetColumnType("v");
        std::cout 
                << t1 << " from TFile\n"
                << t2 << "   from Redefine(...)\n"
                << typeid(float).name() << "\n"
                << typeid(Float_t).name() << "\n"
                << typeid(ROOT::VecOps::RVec<float>).name() << "\n"
                << typeid(ROOT::VecOps::RVec<Float_t>).name() << "\n"
                << ROOT::RDF::RDFInternal::TypeID2TypeName(typeid(ROOT::VecOps::RVec<float>)) << "\n"
                << ROOT::RDF::RDFInternal::TypeID2TypeName(typeid(ROOT::VecOps::RVec<Float_t>)) << "\n"
        ;
        // uncomment the line below to get the error
        // df = df.Vary({"v", "w"}, [] (const ROOT::RVecF& v, const ROOT::RVecF& w) { return ROOT::RVec<ROOT::RVec<ROOT::RVecF>>{{v * 0.9, v * 1.1}, {w * 0.9, w * 1.1}}; }, {"v", "w"}, {"down", "up"}, "variation");
        return 0;
}

ROOT version

Any

Installation method

Any

Operating system

Any

Additional context

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