%IJK2N Convert spatial indexes to its deposition time index n
%
% Examples:
%   n = ijn2n(3,4,5)
%   
% Define the global variables nl nw nh before calling this function!

% Copyright (C) Jie Zhang (ORCID: 0000-0002-8023-8144) 2019

function n = ijk2n(i,j,k)
global nl nw nh
if isequal(mod(j,2),0)
   n = nl + 1 - i + nl*(j-1) + nl * nw * (k-1);
else
   n = i + nl*(j-1) + nl*nw*(k-1); 
end