Re: 2D hists: slices, bands and projections

From: Rene Brun (Rene.Brun@cern.ch)
Date: Tue Feb 29 2000 - 08:21:01 MET


Dear Pasha,

I am surprised by your question. Root supports ALL projections, bands,
slices facilities of Hbook and many more. Did you look at the TH1 specs
?
You will find:

    virtual void     FitSlicesX(TF1 *f1=0,Int_t binmin=1, Int_t
binmax=0, 
                                Int_t cut=0 ,Option_t *option="QNR");
    virtual void     FitSlicesY(TF1 *f1=0,Int_t binmin=1, Int_t
binmax=0, 
                                Int_t cut=0 ,Option_t *option="QNR");
    virtual void     FitSlicesZ(TF1 *f1=0,Int_t binminx=1, Int_t
binmaxx=0,
                                Int_t binminy=1, Int_t binmaxy=0,
                                Int_t cut=0 ,Option_t *option="QNR");
    virtual Stat_t   Integral();
    virtual Stat_t   Integral(Int_t binx1, Int_t binx2);
    virtual Stat_t   Integral(Int_t binx1, Int_t binx2, Int_t biny1, 
                              Int_t biny2);
    virtual Stat_t   Integral(Int_t binx1, Int_t binx2, Int_t biny1, 
                              Int_t biny2, Int_t binz1, Int_t binz2);
        TProfile    *ProfileX(const char *name="_pfx", Int_t
firstybin=0, 
                              Int_t lastybin=9999, Option_t *option="");
        TProfile    *ProfileY(const char *name="_pfy", Int_t
firstxbin=0, 
                              Int_t lastxbin=9999, Option_t *option="");
            TH1D    *ProjectionX(const char *name="_px", Int_t
firstybin=0,                                    Int_t lastybin=9999,
Option_t *option="");
            TH1D    *ProjectionY(const char *name="_py", Int_t
firstxbin=0,                                    Int_t lastxbin=9999,
Option_t *option="");
            TH1D    *ProjectionZ(const char *name="_pz", Int_t
firstxbin=0,                                    Int_t lastxbin=9999,
Int_t firstybin=0,
                                 Int_t lastybin=9999, Option_t
*option="");
            TH1     *Project3D(Option_t *option="x");


In addition, the Root functions work from an existing 2-d or 3-d
histograms.
No need to prebook the projections, slices, etc as it was the case for
Hbook.

Rene Brun
Pasha Murat (630)840-8237@169G wrote:
> 
> Hi Rooters,
> 
> in old good days of HBOOK 2D histograms had a set of nice facilities of
> slices, banks and projections which were extremely handy for analysis.
> I'm thinking if it is worth having the equivalent functionality in ROOT
> classes - it is certainly true that everybody can easily implement such
> macros for himself, but wouldn't it be nice to have a common set of such
> utilities ?
>                                                 thanks, Pasha



This archive was generated by hypermail 2b29 : Tue Jan 02 2001 - 11:50:20 MET