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"# gr110_logscale\n",
"The logarithmic scale can be applied to either the x-axis, the y-axis, or both axes at the same time.\n",
"When using a logarithmic scale, the data must be positive since the logarithm is undefined for non-positive values and zero.\n",
"\n",
"\n",
"\n",
"**Author:** Emanuele Chiamulera \n",
"This notebook tutorial was automatically generated with ROOTBOOK-izer from the macro found in the ROOT repository on Tuesday, May 19, 2026 at 08:38 PM."
]
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"auto c = new TCanvas(\"c\",\"Reversed graphs\",0,0,900,400);\n",
"c->Divide(2,1);\n",
"c->cd(1);\n",
"\n",
"const Int_t n = 6; //Fill the arrays x and y with the data points\n",
"Double_t x[n], y[n];\n",
"for (Int_t i=0;iSetLineColor(2);\n",
"gr1->SetLineWidth(4);\n",
"gr1->SetMarkerColor(4);\n",
"gr1->SetMarkerStyle(21);\n",
"gr1->SetTitle(\"Graph without log scale\");\n",
"gr1->DrawClone(\"ACP\");"
]
},
{
"cell_type": "markdown",
"id": "f96becb6",
"metadata": {},
"source": [
"The logarithmic scale setting can also be done in a ROOT interactive session."
]
},
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"source": [
"c->cd(2);\n",
"gPad->SetLogy();"
]
},
{
"cell_type": "markdown",
"id": "39dcace4",
"metadata": {},
"source": [
"gPad->SetLogx(); Uncomment this line if log scale is needed on both axes"
]
},
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"id": "1acecbc8",
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"outputs": [],
"source": [
"gr1->SetTitle(\"Graph with y log scale\");\n",
"gr1->Draw(\"ACP\");"
]
},
{
"cell_type": "markdown",
"id": "d20732fd",
"metadata": {},
"source": [
"Draw all canvases "
]
},
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"gROOT->GetListOfCanvases()->Draw()"
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