there are two ways:
1) just call for each histogram:
hist->Write(); // see TObject::Write()
to write a histogram in the current file directory.
2) attach all histograms to the current directory
hist->SetDirectory(gDirectory);
and then call:
file->Write();
which will write all objects attached to the files directories to disk.
Probably 1) is easiest in your case.
Cheers, Fons.
Alberto Baldisseri wrote:
>
> Hi rooters,
>
> I have a macro that build some histograms and I would like to save it on
> a file. The standard
> way suggested on the tutorial is to open the file before creating the
> histograms, in that way
> all the histograms are located in the current directory of the open
> file. But, I would like to
> save the histograms AFTER the book+fill.
> When I open the file after the histogram book+fill, the file becomes the
> current directory
> which is empty. There is a way to copy all the histograms to the file
> directory ? Or another
> solution ?
>
> Regards,
>
> Alberto
>
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> | Alberto BALDISSERI | Tel : (33-1) 69 08 93 33 |
> | DAPNIA/SPhN, Bat 703 piece 42 | Fax : (33-1) 69 08 75 84 |
> | CEA Saclay | E-mail : baldiss@hep.saclay.cea.fr |
> | F 91191 Gif-sur-Yvette cedex | |
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-- Org: CERN, European Laboratory for Particle Physics. Mail: 1211 Geneve 23, Switzerland Phone: +41 22 7679248 E-Mail: Fons.Rademakers@cern.ch Fax: +41 22 7677910