closest index in matrix between two values

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hello, i have 2d matrix for example:
X = [0 0 0 0 0;
1 1 1 1 1;
0 1 2 1 0;
1 1 1 1 1;
0 0 0 0 0]
i want to get closest index of columns and rows between value 2 and 0. Is there any chance to do this??
Regards
  2 Comments
df df
df df on 8 Jul 2016
i want index of value 0 which is closest to index of value 2 which means i want to get index (3,1) (1,3) (5,3) and (3,5) bcs they are only 2 cells away

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Accepted Answer

Stephen23
Stephen23 on 8 Jul 2016
Edited: Stephen23 on 8 Jul 2016
X = [0 0 0 0 0;
1 1 1 1 1;
0 1 2 1 0;
1 1 1 1 1;
0 0 0 0 0];
[R0,C0] = find(X==0);
[R2,C2] = find(X==2);
Rm = bsxfun(@minus,R0,R2.');
Cm = bsxfun(@minus,C0,C2.');
% Xd = abs(Rm) + abs(Cm);
Xd = sqrt(Rm.^2 + Cm.^2); % this could probably be improved.
[R,~] = find(Xd==min(Xd(:))); % and a tolerance might be useful here...
and the indices of the zeros closest to the two are:
>> [R0(R),C0(R)]
ans =
3 1
1 3
5 3
3 5

More Answers (2)

José-Luis
José-Luis on 8 Jul 2016
X = [0 0 0 0 0;
1 1 1 1 1;
0 1 2 1 0;
1 1 1 1 1;
0 0 0 0 0];
[tx,ty] = find(X==2);
x_dist = abs(tx-(1:size(X,1)));
y_dist = abs(ty-(1:size(X,2)))';
dist_array = bsxfun(@plus,x_dist.^2,y_dist.^2);
[ix,iy] = find(dist_array == min(dist_array(X==0)))

Andrei Bobrov
Andrei Bobrov on 8 Jul 2016
z = bwdist(X == 2).*(X == 0);
[ii,jj] = find(z == min(z(z~=0)));
  2 Comments
Stephen23
Stephen23 on 8 Jul 2016
Note: requires the Image Processing Toolbox.
Andrei Bobrov
Andrei Bobrov on 8 Jul 2016
Hi Stephen! MATLAB without Image... whot is it? :)

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