Reading root file in compiled code

ROOT
1

Hi,

I am reading a root file and getting the histograms with this code:
Root version 5.18/00


int fillEigenvector(char *theoryfile,char *hname){

  TH1F** isto=0;
  isto = new TH1F*[42];
  TFile *f=TFile::Open(theoryfile);


for (int k=0; k<41; k++){

        char dirname[12];

        f->cd(dirname);

        isto[k] = new TH1F;

        isto[k] =(TH1F)(gDirectory->Get(hname));

}


// ... ... ...
//

return 1;
}

the problem is that if I call this function in interactive mode (with the interpreter) it works
but when I try to compile the code in which I call this function I got this error message:

no matching function for call to `TH1F::TH1F(TObject*)’

It is clear which is the meaning of the error but I don’t know how to avoid this;

I also tried with something like:

isto[k] = (TH1F)f->Get(hname);
or
isto[k] = (TH1F) f->FindObjectAny(hname);

but I get the same error.

cheers,
Francesco

p.s.
I compiled with
g++ analysis.cpp -o analysis root-config --cflags --libs

2

Hi,

Just try to replace:

by:

(note the TH1F *)

Cheers, Bertrand.

3

thank you, it works…

sorry… now I understood…
my stupid mistake

but why it works with the interpreter?

cheers,
Francesco

4

Hi,

because the interpreter tries to be helpful and interprets what you type, to get you past these basic mistakes.

Cheers, Axel.