Re: TTree with user defined class

Hello Bob,

Okp. So, if you are compiling that way, this should work right away. I am using ROOT Version 5.27/04, it works alright. One thing, don't call your routine "main()", because there is already a main running by the time you call CINT. Call it something different. What version of ROOT are you using ?

John

Bob wrote:
> Thanks John,
>
> First I moved the class definition to Sample.h then I choose the ACLiC
> option to generate the dictionary (.L Sample.h+). I got two new file
> Sample_h.so and Sample_h.d
>
> When I try to run the program I have exactly the same error :
> Error in <TTree::Branch>: The pointer specified for debug is not of a
> class or type known to ROOT.
>
> I also tried to link ttree_write.o against the library Sample_h.so but
> without success, should I keep going in this way ? I'm a bit lost !
>
> Thanks,
>
> Bob
>
> 2010/9/27 John Idarraga <idarraga_at_cern.ch>:
>
>> Hello Bob,
>>
>> Yeah, you need a dictionary, a couple of macros in your source file and
>> that's it. Check this out
>>
>> http://root.cern.ch/drupal/content/interacting-shared-libraries-rootcint
>>
>> if you have any trouble let me know,
>>
>> John Idarraga
>>
>> Bob wrote:
>>
>>> Hello,
>>>
>>> I'm a Root beginner, I'm trying to save a class to a TTree. Until now
>>> I managed to store and read "simple" type like int and STL objects,
>>> but not homemade objects.
>>>
>>> I'm made a short example :
>>>
>>> Code snippet :
>>>
>>> #include <TFile.h>
>>> #include <TTree.h>
>>> #include <vector>
>>> #include <iostream>
>>>
>>> class Sample {
>>> public:
>>> int i;
>>> std::vector<int> hits;
>>> };
>>>
>>> int main() {
>>> Sample *s = new Sample();
>>> TFile *f1 = new TFile("debug.root","RECREATE");
>>> if (f1->IsZombie()) {
>>> std::cerr << "! Unable to create debug.root" << std::endl;
>>> return -1;
>>> }
>>> TTree *tree = new TTree("T","Debug");
>>> //Case C
>>> // MyClass object;
>>> // TBranch *branch = tree->Branch(branchname, &object,
>>> bufsize, splitlevel)
>>> //
>>> tree->Branch("debug",s);
>>> for(int j=0;j<10;j++) {
>>> s->hits.empty();
>>> for(int i=0;i<100;i++) {
>>> s->hits.push_back(42+i);
>>> }
>>> tree->Fill();
>>> }
>>> f1->Write();
>>> delete s;
>>> delete tree;
>>> delete f1;
>>> return 0;
>>> }
>>>
>>> I compile with
>>>
>>> g++ -Wall -pedantic -pthread -m32
>>> -I/home/bob/root/root-5.26.00d/include -c ttree_write.cxx -o
>>> ttree_write.o
>>>
>>> and I link with
>>>
>>> g++ -L/home/bob/root/root-5.26.00d/lib -lNew -lCore -lCint -lRIO
>>> -lNet -lHist -lGraf -lGraf3d -lGpad -lTree -lRint -lPostscript
>>> -lMatrix -lPhysics -lMathCore -lThread -pthread -lm -ldl -rdynamic
>>> -L/home/bob/root/root-5.26.00d/lib -lNew -lCore -lCint -lRIO -lNet
>>> -lHist -lGraf -lGraf3d -lGpad -lTree -lRint -lPostscript -lMatrix
>>> -lPhysics -lMathCore -lThread -lGui -pthread -lm -ldl -rdynamic
>>> ttree_write.o -o ttree_write
>>>
>>> When I run the program I got
>>> Error in <TTree::Branch>: The pointer specified for debug is not of a
>>> class known to ROOT
>>>
>>> I'm sure that I miss an important step but I'm out of ideas ! Any tips ?
>>>
>>>
>>>
>>
>
>
Received on Mon Sep 27 2010 - 13:30:24 CEST