Your two projections h2 and h3 have the same number of bins,
eg you can do h3->Divide(h2);
However, you call the default constructor for h4. h4 does not have the
same number of bins as h2 and h3.
Instead of
TH2D *h4 = new TH2D;
h4->Divide(h3, h2);
do
TH2D *h4 = (TH2D*)h2->Clone();
h4->Divide(h3, h2);
Rene Brun
Thomas Bretz wrote:
>
> Hi,
>
> I have a
> Double_t x[5] = { 0, 1, 2, 3, 4 };
> TH3D fHist("", "", 4, x, 4, x, 4, x);
> and do:
> fHist.GetZaxis()->SetRange(3, 4);
> TH1 *h2 = fHist.Project3D("xy_off"); //, -1, 9999, "E");
>
> fHist.GetZaxis()->SetRange(1,2);
> TH1 *h3 = fHist.Project3D("xy_on"); //, -1, 9999, "E");
>
> TH2D *h4 = new TH2D;
> h4->Divide(h3, h2);
>
> And I get
> Attempt to divide histograms with different number of bins...
>
> What am I doing wrong? I would expect to have two projections to have
> the same binning...
>
> Thomas.
This archive was generated by hypermail 2b29 : Sun Jan 02 2005 - 05:50:06 MET