include/root/THnBase.h

0001 // @(#)root/hist:$Id$
0002 // Author: Axel Naumann (2011-12-20)
0003
0004 /*************************************************************************
0005  * Copyright (C) 1995-2012, Rene Brun and Fons Rademakers.               *
0006  * All rights reserved.                                                  *
0007  *                                                                       *
0008  * For the licensing terms see $ROOTSYS/LICENSE.                         *
0009  * For the list of contributors see $ROOTSYS/README/CREDITS.             *
0010  *************************************************************************/
0011
0012 #ifndef ROOT_THnBase
0013 #define ROOT_THnBase
0014
0015 /*************************************************************************
0016
0017  THnBase: Common base class for n-dimensional histogramming.
0018  Defines interfaces and algorithms.
0019
0020 *************************************************************************/
0021
0022
0023 #include "TNamed.h"
0024 #include "TMath.h"
0025 #include "TFitResultPtr.h"
0026 #include "TObjArray.h"
0027 #include "TArrayD.h"
0028 #include <vector>
0029
0030
0031 class TAxis;
0032 class TH1;
0033 class TH1D;
0034 class TH2D;
0035 class TH3D;
0036 class TF1;
0037 class THnIter;
0038
0039 namespace ROOT {
0040 namespace Internal {
0041    class THnBaseBinIter;
0042 }
0043 }
0044
0045 class THnBase: public TNamed {
0046 protected:
0047    Int_t      fNdimensions;  ///<  Number of dimensions
0048    TObjArray  fAxes;         ///<  Axes of the histogram
0049    TObjArray  fBrowsables;   ///<! Browser-helpers for each axis
0050    Double_t   fEntries;      ///<  Number of entries, spread over chunks
0051    Double_t   fTsumw;        ///<  Total sum of weights
0052    Double_t   fTsumw2;       ///<  Total sum of weights squared; -1 if no errors are calculated
0053    TArrayD    fTsumwx;       ///<  Total sum of weight*X for each dimension
0054    TArrayD    fTsumwx2;      ///<  Total sum of weight*X*X for each dimension
0055    std::vector<Double_t> fIntegral; ///<! vector with bin weight sums
0056    enum {
0057       kNoInt,
0058       kValidInt,
0059       kInvalidInt
0060    } fIntegralStatus;        ///<! status of integral
0061
0062  protected:
0063     THnBase() : fNdimensions(0), fEntries(0), fTsumw(0), fTsumw2(-1.), fIntegral(), fIntegralStatus(kNoInt) {}
0064
0065     THnBase(const char *name, const char *title, Int_t dim, const Int_t *nbins, const Double_t *xmin,
0066             const Double_t *xmax);
0067
0068     THnBase(const char* name, const char* title, const std::vector<TAxis>& axes);
0069
0070     THnBase(const char *name, const char *title, Int_t dim, const Int_t *nbins,
0071             const std::vector<std::vector<double>> &xbins);
0072
0073     THnBase(const THnBase &other);
0074
0075     THnBase &operator=(const THnBase &other);
0076
0077     THnBase(THnBase &&other);
0078
0079     THnBase &operator=(THnBase &&other);
0080
0081     void UpdateXStat(const Double_t *x, Double_t w = 1.)
0082     {
0083        if (GetCalculateErrors()) {
0084           for (Int_t d = 0; d < fNdimensions; ++d) {
0085              const Double_t xd = x[d];
0086              fTsumwx[d] += w * xd;
0087              fTsumwx2[d] += w * xd * xd;
0088           }
0089        }
0090     }
0091
0092    /// Increment the statistics due to filled weight "w",
0093    void FillBinBase(Double_t w) {
0094       fEntries += 1;
0095       if (GetCalculateErrors()) {
0096          fTsumw += w;
0097          fTsumw2 += w*w;
0098       }
0099       fIntegralStatus = kInvalidInt;
0100    }
0101
0102    virtual void InitStorage(Int_t* nbins, Int_t chunkSize) = 0;
0103    void Init(const char* name, const char* title,
0104              const TObjArray* axes, Bool_t keepTargetAxis,
0105              Int_t chunkSize = 1024 * 16);
0106    THnBase* CloneEmpty(const char* name, const char* title,
0107                        const TObjArray* axes, Bool_t keepTargetAxis) const;
0108    virtual void Reserve(Long64_t /*nbins*/) {}
0109    virtual void SetFilledBins(Long64_t /*nbins*/) {};
0110
0111    Bool_t CheckConsistency(const THnBase *h, const char *tag) const;
0112    TH1* CreateHist(const char* name, const char* title,
0113                    const TObjArray* axes, Bool_t keepTargetAxis) const;
0114    TObject* ProjectionAny(Int_t ndim, const Int_t* dim,
0115                           Bool_t wantNDim, Option_t* option = "") const;
0116    Bool_t PrintBin(Long64_t idx, Int_t* coord, Option_t* options) const;
0117    void AddInternal(const THnBase* h, Double_t c, Bool_t rebinned);
0118    THnBase* RebinBase(Int_t group) const;
0119    THnBase* RebinBase(const Int_t* group) const;
0120    void ResetBase(Option_t *option= "");
0121
0122    static THnBase* CreateHnAny(const char* name, const char* title,
0123                                const TH1* h1, Bool_t sparse,
0124                                Int_t chunkSize = 1024 * 16);
0125    static THnBase* CreateHnAny(const char* name, const char* title,
0126                                const THnBase* hn, Bool_t sparse,
0127                                Int_t chunkSize = 1024 * 16);
0128
0129  public:
0130    ~THnBase() override;
0131
0132    TObjArray* GetListOfAxes() { return &fAxes; }
0133    const TObjArray* GetListOfAxes() const { return &fAxes; }
0134    TAxis* GetAxis(Int_t dim) const { return (TAxis*)fAxes[dim]; }
0135
0136    TFitResultPtr Fit(TF1 *f1 ,Option_t *option = "", Option_t *goption = "");
0137    TList* GetListOfFunctions() { return nullptr; }
0138
0139    virtual ROOT::Internal::THnBaseBinIter* CreateIter(Bool_t respectAxisRange) const = 0;
0140
0141    virtual Long64_t GetNbins() const = 0;
0142    Double_t GetEntries() const { return fEntries; }
0143    Double_t GetWeightSum() const { return fTsumw; }
0144    Int_t    GetNdimensions() const { return fNdimensions; }
0145    Bool_t   GetCalculateErrors() const { return fTsumw2 >= 0.; }
0146
0147    /// Calculate errors (or not if "calc" == kFALSE)
0148    void     CalculateErrors(Bool_t calc = kTRUE) {
0149       if (calc) Sumw2();
0150       else fTsumw2 = -1.;
0151    }
0152
0153    Long64_t Fill(const Double_t *x, Double_t w = 1.) {
0154       UpdateXStat(x, w);
0155       Long64_t bin = GetBin(x, kTRUE /*alloc*/);
0156       FillBin(bin, w);
0157       return bin;
0158    }
0159    Long64_t Fill(const char* name[], Double_t w = 1.) {
0160       Long64_t bin = GetBin(name, kTRUE /*alloc*/);
0161       FillBin(bin, w);
0162       return bin;
0163    }
0164
0165    /// Fill with the provided variadic arguments.
0166    /// The number of arguments must be equal to the number of histogram dimensions or, for weighted fills, to the
0167    /// number of dimensions + 1; in the latter case, the last function argument is used as weight.
0168    /// A separate `firstval` argument is needed so the compiler does not pick this overload instead of the non-templated
0169    /// Fill overloads
0170    template <typename... MoreTypes>
0171    Long64_t Fill(Double_t firstval, MoreTypes... morevals)
0172    {
0173       const std::array<double, 1 + sizeof...(morevals)> x{firstval, static_cast<double>(morevals)...};
0174       if (Int_t(x.size()) == GetNdimensions()) {
0175          // without weight
0176          return Fill(x.data());
0177       } else if (Int_t(x.size()) == (GetNdimensions() + 1)) {
0178          // with weight
0179          return Fill(x.data(), x.back());
0180       } else {
0181          Error("Fill", "Wrong number of arguments for number of histogram axes.");
0182       }
0183
0184       return -1;
0185    }
0186
0187    virtual void FillBin(Long64_t bin, Double_t w) = 0;
0188
0189    void SetBinEdges(Int_t idim, const Double_t* bins);
0190    Bool_t IsInRange(Int_t *coord) const;
0191    Double_t GetBinError(const Int_t *idx) const { return GetBinError(GetBin(idx)); }
0192    Double_t GetBinError(Long64_t linidx) const { return TMath::Sqrt(GetBinError2(linidx)); }
0193    void SetBinError(const Int_t* idx, Double_t e) { SetBinError(GetBin(idx), e); }
0194    void SetBinError(Long64_t bin, Double_t e) { SetBinError2(bin, e*e); }
0195    void AddBinContent(const Int_t* x, Double_t v = 1.) { AddBinContent(GetBin(x), v); }
0196    void SetEntries(Double_t entries) { fEntries = entries; }
0197    void SetTitle(const char *title) override;
0198
0199    std::vector<Double_t> GetBinCenter(const std::vector<Int_t> &idx) const;
0200
0201    Double_t GetBinContent(const Int_t *idx) const { return GetBinContent(GetBin(idx)); } // intentionally non-virtual
0202    virtual Double_t GetBinContent(Long64_t bin, Int_t* idx = nullptr) const = 0;
0203    virtual Double_t GetBinError2(Long64_t linidx) const = 0;
0204    virtual Long64_t GetBin(const Int_t* idx) const = 0;
0205    virtual Long64_t GetBin(const Double_t* x) const = 0;
0206    virtual Long64_t GetBin(const char* name[]) const = 0;
0207    virtual Long64_t GetBin(const Int_t* idx, Bool_t /*allocate*/ = kTRUE) = 0;
0208    virtual Long64_t GetBin(const Double_t* x, Bool_t /*allocate*/ = kTRUE) = 0;
0209    virtual Long64_t GetBin(const char* name[], Bool_t /*allocate*/ = kTRUE) = 0;
0210
0211    void SetBinContent(const Int_t* idx, Double_t v) { SetBinContent(GetBin(idx), v); } // intentionally non-virtual
0212    virtual void SetBinContent(Long64_t bin, Double_t v) = 0;
0213    virtual void SetBinError2(Long64_t bin, Double_t e2) = 0;
0214    virtual void AddBinError2(Long64_t bin, Double_t e2) = 0;
0215    virtual void AddBinContent(Long64_t bin, Double_t v = 1.) = 0;
0216
0217    Double_t GetSumw() const  { return fTsumw; }
0218    Double_t GetSumw2() const { return fTsumw2; }
0219    Double_t GetSumwx(Int_t dim) const  { return fTsumwx[dim]; }
0220    Double_t GetSumwx2(Int_t dim) const { return fTsumwx2[dim]; }
0221
0222    /// Project all bins into a 1-dimensional histogram,
0223    /// keeping only axis "xDim".
0224    /// If "option" contains:
0225    ///  - "E" errors will be calculated.
0226    ///  - "A" ranges of the taget axes will be ignored.
0227    ///  - "O" original axis range of the taget axes will be
0228    ///    kept, but only bins inside the selected range
0229    ///    will be filled.
0230    TH1D*    Projection(Int_t xDim, Option_t* option = "") const {
0231       return (TH1D*) ProjectionAny(1, &xDim, false, option);
0232    }
0233
0234    /// Project all bins into a 2-dimensional histogram,
0235    /// keeping only axes "xDim" and "yDim".
0236    ///
0237    /// WARNING: just like TH3::Project3D("yx") and TTree::Draw("y:x"),
0238    /// Projection(y,x) uses the first argument to define the y-axis and the
0239    /// second for the x-axis!
0240    ///
0241    /// If "option" contains "E" errors will be calculated.
0242    ///                      "A" ranges of the taget axes will be ignored.
0243    TH2D*    Projection(Int_t yDim, Int_t xDim, Option_t* option = "") const {
0244       const Int_t dim[2] = {xDim, yDim};
0245       return (TH2D*) ProjectionAny(2, dim, false, option);
0246    }
0247
0248    /// Project all bins into a 3-dimensional histogram,
0249    /// keeping only axes "xDim", "yDim", and "zDim".
0250    /// If "option" contains:
0251    ///  - "E" errors will be calculated.
0252    ///  - "A" ranges of the taget axes will be ignored.
0253    ///  - "O" original axis range of the taget axes will be
0254    ///    kept, but only bins inside the selected range
0255    ///    will be filled.
0256    TH3D*    Projection(Int_t xDim, Int_t yDim, Int_t zDim, Option_t* option = "") const {
0257       const Int_t dim[3] = {xDim, yDim, zDim};
0258       return (TH3D*) ProjectionAny(3, dim, false, option);
0259    }
0260
0261    THnBase* ProjectionND(Int_t ndim, const Int_t* dim,
0262                          Option_t* option = "") const {
0263       return (THnBase*)ProjectionAny(ndim, dim, kTRUE /*wantNDim*/, option);
0264    }
0265
0266    Long64_t   Merge(TCollection* list);
0267
0268    void Scale(Double_t c);
0269    void Add(const THnBase* h, Double_t c=1.);
0270    void Add(const TH1* hist, Double_t c=1.);
0271    void Multiply(const THnBase* h);
0272    void Multiply(TF1* f, Double_t c = 1.);
0273    void Divide(const THnBase* h);
0274    void Divide(const THnBase* h1, const THnBase* h2, Double_t c1 = 1., Double_t c2 = 1., Option_t* option="");
0275    void RebinnedAdd(const THnBase* h, Double_t c=1.);
0276
0277    virtual void Reset(Option_t* option = "") = 0;
0278    virtual void Sumw2() = 0;
0279
0280    Double_t ComputeIntegral();
0281    void GetRandom(Double_t *rand, Bool_t subBinRandom = kTRUE);
0282    Double_t Integral(Bool_t respectAxisRange) const;
0283
0284    void Print(Option_t* option = "") const override;
0285    void PrintEntries(Long64_t from = 0, Long64_t howmany = -1, Option_t* options = nullptr) const;
0286    void PrintBin(Int_t* coord, Option_t* options) const {
0287       PrintBin(-1, coord, options);
0288    }
0289    void PrintBin(Long64_t idx, Option_t* options) const;
0290
0291    void Browse(TBrowser *b) override;
0292    Bool_t IsFolder() const override { return kTRUE; }
0293
0294    //void Draw(Option_t* option = "");
0295
0296    ClassDefOverride(THnBase, 1); // Common base for n-dimensional histogram
0297
0298    friend class THnIter;
0299 };
0300
0301 namespace ROOT {
0302 namespace Internal {
0303    // Helper class for browsing THnBase objects
0304    class THnBaseBrowsable: public TNamed {
0305    public:
0306       THnBaseBrowsable(THnBase* hist, Int_t axis);
0307       ~THnBaseBrowsable() override;
0308       void Browse(TBrowser *b) override;
0309       Bool_t IsFolder() const override { return kFALSE; }
0310
0311    private:
0312       THnBase* fHist; // Original histogram
0313       Int_t    fAxis; // Axis to visualize
0314       TH1*     fProj; // Projection result
0315       ClassDefOverride(THnBaseBrowsable, 0); // Browser-helper for THnBase
0316    };
0317
0318    // Base class for iterating over THnBase bins
0319    class THnBaseBinIter {
0320    public:
0321       THnBaseBinIter(Bool_t respectAxisRange):
0322          fRespectAxisRange(respectAxisRange), fHaveSkippedBin(kFALSE) {}
0323       virtual ~THnBaseBinIter();
0324       Bool_t HaveSkippedBin() const { return fHaveSkippedBin; }
0325       Bool_t RespectsAxisRange() const { return fRespectAxisRange; }
0326
0327       virtual Int_t GetCoord(Int_t dim) const = 0;
0328       virtual Long64_t Next(Int_t* coord = nullptr) = 0;
0329
0330    protected:
0331       Bool_t fRespectAxisRange;
0332       Bool_t fHaveSkippedBin;
0333    };
0334 }
0335 }
0336
0337 class THnIter: public TObject {
0338 public:
0339    THnIter(const THnBase* hist, Bool_t respectAxisRange = kFALSE):
0340       fIter(hist->CreateIter(respectAxisRange)) {}
0341    ~THnIter() override;
0342
0343    /// Return the next bin's index.
0344    /// If provided, set coord to that bin's coordinates (bin indexes).
0345    /// I.e. coord must point to Int_t[hist->GetNdimensions()]
0346    /// Returns -1 when all bins have been visited.
0347    Long64_t Next(Int_t* coord = nullptr) {
0348       return fIter->Next(coord);
0349    }
0350
0351    Int_t GetCoord(Int_t dim) const { return fIter->GetCoord(dim); }
0352    Bool_t HaveSkippedBin() const { return fIter->HaveSkippedBin(); }
0353    Bool_t RespectsAxisRange() const { return fIter->RespectsAxisRange(); }
0354
0355 private:
0356    ROOT::Internal::THnBaseBinIter* fIter;
0357    ClassDefOverride(THnIter, 0); //Iterator over bins of a THnBase.
0358 };
0359
0360 #endif //  ROOT_THnBase