or
variable bin size and your desired dimension. These constructors append the
created TEfficiency object to the current directory. So it will be written
automatically to a file during the next <a
    href="http://root.cern.ch/root/html/TFile.html#TFile:Write">TFile::Write</a>
    command.</li>
    <li>Example 1: create a twodimensional TEfficiency object with 10
    bins along X and 20 bins along Y:
    <pre>
TEfficiency* pEff = new TEfficiency("eff","my efficiency;x;y;#epsilon",10,0,10,20,-5,5);
</pre>
  