[ROOT] TTree in nonsplit mode

From: Anton Fokin (anton.fokin@smartquant.com)
Date: Sun Feb 25 2001 - 13:09:56 MET 

Hi Rene and rooters,

I have already asked this question but got no answer.

I have THistoricalData class derived from TObject. I have a tree and write
objects of this class in the tree in NONSPLIT mode in a file with NO
COMPRESSION level set.

--

  fHistoricalData = new THistoricalData();

  TTree *Tree = new TTree(Asset->GetName(), "Asset quote tree");

  Int_t SplitMode = 0;

  Tree->Branch("HistoricalData", "THistoricalData", &fHistoricalData,
32*1024, SplitMode);

  Tree->Write(Asset->GetName());

--

Here is a simple bin dump of the resulting file (sorry if it may cause beeps
on some old terminals).

Question: Why ROOT writes class name in the beginning of every record? From
several hundreds of KB of raw data I get 5MB ROOT file !!!

Regards,
Anton

k(    ¤THistoricalData @  2 d        @   d  @Aç  Aç  Aë  Aå  Aç   T
¤T
}     ¤THistoricalData @  2 d        @   d  JAè  Aè  Aì  Aè  Aè   ¦_
¤T
uX    ¤THistoricalData @  2 d        @   d  QAç  Aç  Aê  Aà  Aç     !_
¤
_L    ¤THistoricalData @  2 d        @   d  ^AàüAàüAë  AäüAàü -ä
¤T
0n    ¤THistoricalData @  2 d        @   d  cAé  Aé  Aå  AÇüAé   ±£
¤T
+ê    ¤THistoricalData @  2 d        @   d  fA}A}Aü  A|  A} _@
¤T
Å_    ¤THistoricalData @  2 d        @   d  qAuAuAyAt  Au ¤$É
¤T
¿    ¤THistoricalData @  2 d        @   d  tAkAkAmAj  Ak §än
¤TH
°    ¤THistoricalData @  2 d        @   d  zA[A[A^  AP  A[ rt
¤TH
        Ç    ¤THistoricalData @  2 d        @   d  ÇA[A[A^  AZ  A[
Y
+    ¤THistoricalData @  2 d        @   d  ¦A«  A«  A_  A¼  A«   ±
¤T
4¶    ¤THistoricalData @  2 d        @   d  +A»üA»üA_ +A«  A»ü I@
¤T
++    ¤THistoricalData @  2 d        @   d !Aö  Aö  Aò  Aæ  Aö   vP
¤T
R(    ¤THistoricalData @  2 d        @   d !
¤T




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