import rootnotes

from ROOT import TCanvas, TFormula, TF1
from ROOT import gROOT, gObjectTable
c1 = rootnotes.default_canvas()

form1 = TFormula( 'form1', 'sqrt(abs(x))' )
form1.Eval( 2 )
form1.Eval( -45 )

fun1 = TF1( 'fun1', 'abs(sin(x)/x)', 0, 10 )
c1.SetGridx()
c1.SetGridy()
fun1.Draw()
c1

canvas = TCanvas("icanvas", "icanvas", 800, 600)