TArrayI and AddFriend

ROOT
1

Hi,
I have defined two classes, one of them, say ItemData, contain a *TArrayI parameter. Then I have create two TFile, each one with a TTree; one of the TTree is filled with ItemData objects. The strange situation is the following:

  1. if I read the files separarately i can read them both
  2. if I open the two files and I make the two TTree friends I cannot even make a GetEntry(#), but doing some changes to the IdemData class (*TArrayI change to TArray) I can again read them both.

I have attached a test script which should show the situation; commenting out the defined line you can test one situation or another.

Thanks
TArrayTest.c (3.7 KB)

2

Hi,

The problem is that you default constructor do not intialize the data member (this is essential!):

In addition to NOT use

from within a function. This should only be used on the command line or in an unnamed macro (i.e. no function).

Cheers,
Philippe.

3

sorry but It does not work anyway… please don’t blame at me but have you verified your solution rigth on the code i submitted to you? i did and the result was the usual…

thanks

4

Indeed I did!
Note that since you did not mention the version of ROOT nor the platform, I assume the latest version. So first try with ROOT v4.02/00.

Also you should actuall compile your macro (which means you need to add ClassDef to your classes).

Cheers,
Philippe

5

Well… you was rigth it was another mistakes of mine.

Thanks for your patience :slight_smile: