This is an easy one.
Let's say you have non-uniformly sampled data t, x, y. You want to find uniformly distributed values for these now.
I am assuming that t = f(x, y).
First we can define the the uniform grid we want the answers on. This usually would be like:
x = rand(100, 1);
y = rand(100, 1);
t = (x + y).^2;
% spacing
divUnit = 0.01;
xUnif = min(x) : divUnit : max(x);
yUnif = min(y) : divUnit : max(y);
% obtain the regural grid by MESHGRIDing the regularly spaced vectors
[X, Y] = meshgrid(xUnif, yUnif);
% interpolate 't' on this uniform grid
intObj = TriScatteredInterp(x, y, t);
T = intObj(X, Y);
% plot what we have
figure;
scatter3(x, y, t);
hold on;
surf(X, Y, T);
