epic-analysis/src/Hist4D.h

0001 // SPDX-License-Identifier: LGPL-3.0-or-later
0002 // Copyright (C) 2023 Duane Byer
0003
0004 #pragma once
0005
0006 #include <TROOT.h>
0007 #include <TNamed.h>
0008 #include <TPad.h>
0009 #include <TAxis.h>
0010 #include <TH2D.h>
0011 #include <TMath.h>
0012 #include <TFrame.h>
0013 #include <stdexcept>
0014
0015 // Convenience class for plotting 4d histogram. Can't derive from TH1 because
0016 // some of the virtual methods are only designed with up to 3 dimensions in
0017 // mind.
0018 class Hist4D : public TNamed {
0019 public:
0020     // TODO: Store a TAxis object for each of the 4 axes, then copy it into the
0021     // sub-histograms as they are constructed. This also allows the _axes
0022     // variable to be eliminated so that it is only constructed on Draw.
0023     // To accomplish this, chain:
0024     //  * PadtoX
0025     //  * XtoPixel
0026     //  * UtoPixel (then reverse it)
0027     // Should look like XtoPixel(XtoPad(bin)) / UtoPixel(1).
0028     TAxis* _w_axis = nullptr;
0029     TAxis* _x_axis = nullptr;
0030     TAxis* _y_axis = nullptr;
0031     TAxis* _z_axis = nullptr;
0032     TH2D* _axes = nullptr;
0033     std::vector<TH2D*> _hists;
0034     Double_t _minimum = TMath::QuietNaN();
0035     Double_t _maximum = TMath::QuietNaN();
0036
0037     void CreateHists();
0038     void CreateAxes();
0039
0040 public:
0041     Hist4D() { }
0042     Hist4D(
0043             char const* name, char const* title,
0044             Int_t nbins_w, Double_t const* bins_w,
0045             Int_t nbins_x, Double_t const* bins_x,
0046             Int_t nbins_y, Double_t const* bins_y,
0047             Int_t nbins_z, Double_t const* bins_z);
0048     Hist4D(
0049             char const* name, char const* title,
0050             Int_t nbins_w, Double_t w_lower, Double_t w_upper,
0051             Int_t nbins_x, Double_t x_lower, Double_t x_upper,
0052             Int_t nbins_y, Double_t y_lower, Double_t y_upper,
0053             Int_t nbins_z, Double_t z_lower, Double_t z_upper);
0054         ~Hist4D();
0055
0056     static bool CheckConsistency(Hist4D const* h1, Hist4D const* h2);
0057     static bool CheckAxisLimits(TAxis const* ax1, TAxis const* ax2);
0058     static bool CheckBinLimits(TAxis const* ax1, TAxis const* ax2);
0059     static bool CheckBinLabels(TAxis const* ax1, TAxis const* ax2);
0060
0061     virtual TObject* Clone(char const* new_name = "_clone") const override;
0062
0063     void Fill(Double_t w, Double_t x, Double_t y, Double_t z);
0064     void Fill(Double_t w, Double_t x, Double_t y, Double_t z, Double_t weight);
0065
0066     Double_t GetEntries();
0067
0068     Bool_t IsEmpty() const;
0069
0070     TAxis* GetWaxis() {
0071         return _w_axis;
0072     }
0073     TAxis* GetXaxis() {
0074         return _x_axis;
0075     }
0076     TAxis* GetYaxis() {
0077         return _y_axis;
0078     }
0079     TAxis* GetZaxis() {
0080         return _z_axis;
0081     }
0082
0083     void SetMinimum(Double_t min = TMath::QuietNaN()) {
0084         _minimum = min;
0085     }
0086     void SetMaximum(Double_t max = TMath::QuietNaN()) {
0087         _maximum = max;
0088     }
0089
0090     void Divide(Hist4D* other);
0091     void Scale(Double_t c);
0092
0093     TH2D* ProjectionYZ(char const* pname = "_pyz");
0094     TH2D* ProjectionWX(
0095         char const* pname = "_pwx",
0096         Int_t firstbiny = 0, Int_t lastbiny = -1,
0097         Int_t firstbinz = 0, Int_t lastbinz = -1);
0098     virtual void Draw(char const* options = "col") override {
0099         if (!gPad) {
0100             gROOT->MakeDefCanvas();
0101         }
0102         DrawPad(gPad, options);
0103     }
0104     void DrawPad(TVirtualPad* pad, char const* options = "col");
0105
0106     ClassDefOverride(Hist4D, 1);
0107 };