3D extrapolation without ScatteredInterpolant

Hello,

if got a three vectors of scattered x, y and z data. I need to extrapolate these. My Release is from 2011, so I do not have the ScatteredInterpolant() function in Matlab, to do the Extrapolation. TriScatteredInterp and griddata only interplate but can not extrapolate. I don't want to write a difficult code where i use interp1. Is there a other fuction, which is capable of extrapolating 3D data?

Thank you for your effort