ROOT_528-00b_version: tutorials/graphics/formula1.C Source File

00001 //Display interpreted functions
00002 //Author: Rene Brun
00003 void formula1() {
00004    //
00005    // To see the graphics output of this macro, click begin_html <a href="gif/formula1.gif">here</a>. end_html
00006    //
00007    TCanvas *c1 = new TCanvas("c1","Example with Formula",200,10,700,500);
00008    //
00009    // We create a formula object and compute the value of this formula
00010    // for two different values of the x variable.
00011    //
00012    form1 = new TFormula("form1","sqrt(abs(x))");
00013    form1->Eval(2);
00014    form1->Eval(-45);
00015    //
00016    // Create a one dimensional function and draw it
00017    //
00018    fun1 = new TF1("fun1","abs(sin(x)/x)",0,10);
00019    c1->SetGridx();
00020    c1->SetGridy();
00021    fun1->Draw();
00022    c1->Update();
00023    //
00024    // Before leaving this demo, we print the list of objects known to ROOT
00025    //
00026    if (gObjectTable) gObjectTable->Print();
00027 }