{
   TCanvas *cl = new TCanvas("cl","cl",10,10,700,100);
   TLatex Tl; Tl.SetTextFont(43); Tl.SetTextSize(20);
   Tl.DrawText(.1, .5,   "#bar{a} and #vec{a} :"); Tl.DrawLatex(.5, .5, "#bar{a} and #vec{a}");
}