Re: Reading single leaf of vector<> type

Hi Philippe,
Thanks! I just checked out trunk and it works for me now.

Philip

On Monday 25 Oct 2010 14:30:43 Philippe Canal wrote:
> Hi Philip,
>
> This problem has been fixed by revision 36421 of the trunk.
> To work around this problem with older version of ROOT, you will need to
> use MakeSelector or MakeProxy to create a skeleton to access the data
> (and/or use a library defining the class A).
>
> Cheers,
> Philippe.
>
> On 10/19/10 3:40 PM, Philip Rodrigues wrote:
> > Hi roottalk,
> > I have a tree with a branch storing a class 'A' containing a vector data
> > member:
> >
> > class A : public TObject
> > {
> > public:
> > A();
> > double x;
> > std::vector<double> v;
> >
> > ClassDef(A, 1);
> > };
> >
> > I want to access items from the vector v without streaming the whole
> > object off of disk. I can do this for the simple double member (x) via
> > TLeaf, like this:
> >
> > TLeaf* l_x=tree->FindLeaf("x");
> > l_x->GetBranch()->GetEntry(someEntry);
> > double value_read = l_x->GetValue();
> >
> > but the corresponding code for the "v" branch always gives zero.
> >
> > How can I access just the data from the v branch? (It must be possible,
> > since TTree::Draw can do it, and I'm sure I've done it before with other
> > files...)
> >
> > I've attached a test file and macro to show exactly what I'm doing.
> >
> > Thanks,
> > Philip
>
Received on Mon Oct 25 2010 - 22:21:00 CEST