MATLAB: Calculating a few elements of a table, using a different equation

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Hello!
Let's say that i am calculating every element of a 100X300 table by using equation A I use two for loops for i=1:100 for j=1:300 element(i,j)=… (it is the equation A) end end equation A involves the neighboring elements What if, a few elements of the table must be calculated with a different equation, equation B and this must happen inside the two for loops
for example elements (49,81) (49,82) (50,81) (50,82) (51,81) (51,82) (52,81) (52,82) i could use if and elseif function for every single element, like if i==49 && j==81 element(i,j)=…equation B elseif i==50 && j==81 element(i,j)=…equation B …
…
end Is there another, better way to do it ???
Thanks a lot!

Best Answer

a = 49:52
b = 81:82
ii = fullfact([numel(b) numel(a)])
for jj = 1:size(ii,1)
    element(a(ii(jj,2)),b(ii(jj,1))) = ...equation;
end
or
[b1,a1] = ndgrid(b,a);
ii = a1(:);
jj = b1(:);
for ij = 1:numel(ii)
    element(ii(ij),jj(ij)) = ...equation;
end
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