Data smoothing function in new version of TecPlot

[mimu88]

Hi,
I am pretty new to TecPlot and this community so sorry in advance if my question seems silly.
I am using Tecplot 360 EX 2015 R2 and I am trying to smooth my 3d data. According to the Tecplot manual I should find the smoothing function under Data -> Alter -> smooth. However, the only thing under the Alter tab is "Specify Equation". Anyone can tell me why I don't see the smoothing function and where can I find it? Thank you!