TGraph* graph = new TGraph(); // fill TGraph with some data points double x, y; int i = 3; graph->GetPoint(i, x, y); cout << "Point at index " << i << ": (" << x << ", " << y << ")" << endl;
TGraph* graph = new TGraph(); // fill TGraph with some data points double x = 3.5, y; int i = graph->GetClosestPoint(x); graph->GetPoint(i, x, y); cout << "Closest point to x=" << x << ": (" << x << ", " << y << ")" << endl;In this example, we create a TGraph object and fill it with some data points. We then use the GetClosestPoint method to find the index of the point closest to the X coordinate 3.5, and finally retrieve the X and Y coordinates of that point using GetPoint. These examples demonstrate how Cpp TGraph GetPoint method is used in scientific data analysis and visualization with ROOT package library.