THStack histogram with markers and no error bars

Newbie
1

Hi,

I am working building a THStack from several histograms on a single canvas. I would like to plot the histograms with only markers and no error bars, Unlike what I see in the attached figure, I would like remove the error bars. Could you help me how to do that. I add the macro that use to plot the histos below:

void processHistograms(const char* filename) {
    // Open the file
    TFile *file = TFile::Open(filename);
    if (!file || file->IsZombie()) {
        std::cerr << "Error opening file: " << filename << std::endl;
        return;
    }

    // Create a canvas
    TCanvas *c = new TCanvas("c", "Canvas", 800, 800);

    gStyle->SetOptTitle(kFALSE);
    gStyle->SetOptStat(0);

    // Create a THStack
    THStack *hStack__Regions = new THStack("hStack_MM_ppLLKX_Regions", "Missing Mass from the Regions on correlation plot; Missing Mass (M_{X}) [MeV/c^{2}]; Counts");

    // Create a legend
    // TLegend *legend = new TLegend(0.7, 0.7, 0.9, 0.9); // Adjust these coordinates as needed


    // An array for choosing colour and marker style
    Int_t a_colour[8] = {1, 2, 3, 4, 6, 7, 8, 9};
    Int_t a_marker[8] = {2, 3, 4, 6, 25, 26, 27, 28};


    // Loop over the histograms
    for (int i = 1; i <= 9; ++i) {
        // Construct the histogram name
        TString histName = Form("hMissingMass_DCACut2_R%d", i);

        // Retrieve the histogram
        TH1F *hist = (TH1F*)file->Get(histName);
        if (!hist) {
            std::cerr << "Histogram not found: " << histName << std::endl;
            continue;
        }

        // Set the maximum of the y-axis
//        hist->SetMaximum(120);
        // Set a unique marker style for each histogram
        hist->SetLineColor(a_colour[i]);
        hist->Scale(0.99999999);
        hist->SetMarkerStyle(a_marker[i]);
        hist->SetMarkerStyle(a_marker[i]);
        hist->SetMarkerColor(a_colour[i]);


        TString legendEntry = Form("Region %d", i);
        hist->SetTitle(legendEntry);

        // Add the histogram to the stack
        hStack_Regions->Add(hist);

        // Add the histogram to the legend
//        legend->AddEntry(hist, legendEntry, "l");

        // Draw the histogram with the "P" option to apply marker styles
//        hist->Draw("SAME PLC PMC");

    }

    // Draw the THStack on the canvas
    hStack_Regions->Draw("NOSTACK, PLC"); // Use "NOSTACK" to draw histograms side by side

    // Draw the legend
//    legend->Draw();

    c->Update();

    gPad->BuildLegend();

    // Close the file
//    file->Close();
}

MM_Regions_errbars.pdf (84.9 KB)

2 
hStack_Regions->Draw("NOSTACK PLC HIST P");`