2D spline interpolation help

I am utterly confused as how to run spline interpolation. i'm working with a 52x3 double matrix called DMAP.

the x and y limits are [min X, max X]=[0 .65];[min X, max X]=[0 .65] and i used a .125 unit grid spacing

>> i=[0:0.125:6.5]
>> j=i
>> [X,Y]=meshgrid(i,j)

I'm supposed to interpolate my data with spline interpolation and then contour it for the grid size. I'm stuck on spline interpolation. Any help is appreciated here!

[Walter Roberson]

is the first column of DMAP x coordinates, and the second is y coordinates? If so, then are the points scattered around, or do they fall onto a grid already?