We do not know. What are the values in sets ? What do you do with the data afterwards?
If sets = {a, b, c, d, e, f} according to the initial assignments of a, b, c, d, e, f that you show, then the total memory for the output of ndgrid is not much, less than 18 megabytes.
However, if you were working in a loop like
a=1:500;
b=1:4;
c=0:2;
d=0:1;
e=0:1;
f=1:15;
for K = 1 : 5
sets = {a, b, c, d, e, f};
[a, b, c, d, e, f] = ndgrid(sets{:});
...
end
then after you do the ndgrid once, because you are overwriting a, b, c, d, e, f, on the second iteration of the loop, the variables would have 360000 elements each, and you would run out of memory trying to ndgrid that .
Re-using variable names for different purposes is poor programming practice that leads to this kind of problem.
