vector_interp_kriging.m is a Kriging interpolation function.
It requires the DACE (Design and Analysis of Computer Experiments) toolbox.
The toolbox was developed by Hans Bruun Nielsen, Soren Nymand
Lophaven and Jacob Sondergaard at Technical University of Denmark.
Download the toolbox from http://www.imm.dtu.dk/
hbn/dace/, expand it,
and put it on the path of MATLAB.