2D Mesh interpolation or calculation effeciency

My question therefore partains code effeciency and readability of the below code. I have a function that uses values the Big mesh to interpolate values in a Small mesh. The Big mesh coordinates are outputs from a diffent calculation. The new outputs should be consistent to the Small Mesh coordinates.

[S1,S2]=meshgrid(0:1:30,40:1:60); % Small Mesh
[B1,B2]=meshgrid(0:10:30,40:10:60); % Big Mesh

M=size(B1,1);
N=size(B1,2);
cell_ij={S1;S2};
spacing=unique(diff(S2));
for i=1:M;
    for j=1:N;
	if i~=j
	   try
                Xs1=find(unique(cell_ij{1,1})==B1(i,j));
                Ys1=find(unique(cell_ij{2,1})==B2(i,j));
                Xs2=find(unique(cell_ij{1,1})==B1(i,end));
                Ys2=find(unique(cell_ij{2,1})==B2(i,end));
                dist=sqrt((Xs1-Xs2)^2+(Ys1-Ys2)^2);
                if dist>0
                    xcords=Xs1:spacing:Xs2
                    ycords=Ys1:spacing:Ys2
                    % the rest of the calculations using the coordinates
                    % new_outputs(i,j)=cal_function(xcords,ycords);
                else
                    disp('too close')
                end
            catch
               disp('skip')
            end
	end
    end
end

Answer 1

[KSSV]

You need not to find the indices.....you have to do interpolation. Read about interp2.

If X, Y, Z are your bigger grid data. And Xi, Yi are smaller grids, which are subset to X, Y.

Zi = interp2(X,Y,Z,Xi,Yi) ; 

[Mau]

Just a clarification that the big and small mesh have different sizes. Additionally, the I intend to compare all index points from the small mesh with the rest of the mesh. I think that the interp2 considers closer points as opposed to an entire mesh.

[KSSV]

The dimensions doesnt matter. You go ahead with interp2.

[Mau]

My input.

[S1,S2]=meshgrid(0:1:30,40:1:60); % Small Mesh
[B1,B2]=meshgrid(0:10:30,40:10:60); % Big Mesh
distB=sqrt((B1-B1).^2+(B2-B2).^2);
distS=interp2(B1,B2,distB,S1,S2);

Output.

all zeros

Thanks.

[KSSV]

Please note that your distB also has all zeros.

[S1,S2]=meshgrid(0:1:30,40:1:60); % Small Mesh
[B1,B2]=meshgrid(0:10:30,40:10:60); % Big Mesh
distB=sqrt((B1).^2+(B2).^2);
distS=interp2(B1,B2,distB,S1,S2);