assign the same vector to be the same cell

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Let's say, I have the matrix:
A=[x,y]=[1 2;1.1 2;1.2 2;1 3;1.1 3;1.2 3;1 4;1.1 4;1.2 4];
If i wanna group all vector having the same value of y coordinate. How can I do that?
Example, the result like that:
Cell1=[1 2
1.1 2
1.2 2]
Cell2=[1 3
1.1 3
1.2 3]
Cell3=[1 4
1.1 4
1.2 4]
  2 Comments
madhan ravi
madhan ravi on 23 Nov 2018
People here put some efforts to help you and you mercilessly close the question without clarifying how rude
ha ha
ha ha on 24 Nov 2018
@ madhan ravi . I'm very sorry. I think I misclick on the button. Very sorry for my mistake.

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Accepted Answer

madhan ravi
madhan ravi on 21 Nov 2018
Edited: madhan ravi on 21 Nov 2018
A=[1 2;1.1 2;1.2 2;1 3;1.1 3;1.2 3;1 4;1.1 4;1.2 4]';
group=reshape(A,2,3,3);
CELL=cell(1,3);
for i = 1:size(group,3)
CELL{i}=group(:,:,i)';
end
celldisp(CELL)
command window:
>>
CELL{1} =
1.0000 2.0000
1.1000 2.0000
1.2000 2.0000
CELL{2} =
1.0000 3.0000
1.1000 3.0000
1.2000 3.0000
CELL{3} =
1.0000 4.0000
1.1000 4.0000
1.2000 4.0000
>>
  1 Comment
ha ha
ha ha on 24 Nov 2018
@ madhan ravi. Why did you know I have 3 cell? I think, you use number "3", because you observe there are 3 cell by visualization. But In general case, we can not know how many cell.

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More Answers (2)

Andrei Bobrov
Andrei Bobrov on 21 Nov 2018
Cell = mat2cell(A,accumarray(findgroups(A(:,2)),1),size(A,2));

Guillaume
Guillaume on 21 Nov 2018
Edited: Guillaume on 21 Nov 2018
Can be done easily with findgroups (or the older unique) and splitapply (or the older accumarray), in just one line:
A = [1 2;1.1 2;1.2 2;1 3;1.1 3;1.2 3;1 4;1.1 4;1.2 4];
C = splitapply(@(rows) {A(rows, :)}, (1:size(A, 1))', findgroups(A(:, 2)));
celldisp(C)
with unique and accumarray, you need two lines as you need the 3rd return value of unique:
A = [1 2;1.1 2;1.2 2;1 3;1.1 3;1.2 3;1 4;1.1 4;1.2 4];
[~, ~, id] = unique(A(:, 2));
C = accumarray(id, (1:size(A, 1))', [], @(rows) {A(rows, :)});
celldisp(C)

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