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    "# tree114_circular\n",
    "Example of a circular Tree\n",
    "\n",
    "Circular Trees are interesting in online real time environments\n",
    "to store the results of the last maxEntries events.\n",
    "for more info, see TTree::SetCircular.\n",
    "Circular trees must be memory resident.\n",
    "\n",
    "\n",
    "\n",
    "\n",
    "**Author:** Rene Brun  \n",
    "<i><small>This notebook tutorial was automatically generated with <a href= \"https://github.com/root-project/root/blob/master/documentation/doxygen/converttonotebook.py\">ROOTBOOK-izer</a> from the macro found in the ROOT repository  on Tuesday, May 19, 2026 at 08:18 PM.</small></i>"
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     "text": [
      "******************************************************************************\n",
      "*Tree    :T         : test circular buffers                                  *\n",
      "*Entries :    18977 : Total =          420932 bytes  File  Size =          0 *\n",
      "*        :          : Tree compression factor =   1.00                       *\n",
      "******************************************************************************\n",
      "*Br    0 :px        : px/F                                                   *\n",
      "*Entries :    18977 : Total  Size=      76529 bytes  One basket in memory    *\n",
      "*Baskets :        0 : Basket Size=      32000 bytes  Compression=   1.00     *\n",
      "*............................................................................*\n",
      "*Br    1 :py        : px/F                                                   *\n",
      "*Entries :    18977 : Total  Size=      76529 bytes  One basket in memory    *\n",
      "*Baskets :        0 : Basket Size=      32000 bytes  Compression=   1.00     *\n",
      "*............................................................................*\n",
      "*Br    2 :pz        : px/F                                                   *\n",
      "*Entries :    18977 : Total  Size=      76529 bytes  One basket in memory    *\n",
      "*Baskets :        0 : Basket Size=      32000 bytes  Compression=   1.00     *\n",
      "*............................................................................*\n",
      "*Br    3 :random    : random/D                                               *\n",
      "*Entries :    18977 : Total  Size=     152469 bytes  One basket in memory    *\n",
      "*Baskets :        0 : Basket Size=      32000 bytes  Compression=   1.00     *\n",
      "*............................................................................*\n",
      "*Br    4 :i         : i/s                                                    *\n",
      "*Entries :    18977 : Total  Size=      38565 bytes  One basket in memory    *\n",
      "*Baskets :        0 : Basket Size=      32000 bytes  Compression=   1.00     *\n",
      "*............................................................................*\n"
     ]
    }
   ],
   "source": [
    "TRandom r;\n",
    "Float_t px,py,pz;\n",
    "Double_t randomNum;\n",
    "UShort_t i;\n",
    "auto T = new TTree(\"T\", \"test circular buffers\");\n",
    "T->Branch(\"px\", &px, \"px/F\");\n",
    "T->Branch(\"py\", &py, \"px/F\");\n",
    "T->Branch(\"pz\", &pz, \"px/F\");\n",
    "T->Branch(\"random\", &randomNum, \"random/D\");\n",
    "T->Branch(\"i\", &i, \"i/s\");\n",
    "T->SetCircular(20000); // keep a maximum of 20000 entries in memory\n",
    "for (i = 0; i < 65000; i++) {\n",
    "   r.Rannor(px, py);\n",
    "   pz = px * px + py * py;\n",
    "   randomNum = r.Rndm();\n",
    "   T->Fill();\n",
    "}\n",
    "T->Print();"
   ]
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