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Break a big matrix into cell array based on repetitive number in one of the matrix columns

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I have a matrix of 383533*3 doubles, column 2 includes some repetitive numbers, like 2.5483e+06 here, which is similar for 600 raw. how I can break down this big matrix into cells which each cell includes 3 columns of numbers which second column is constant for each cell.

Accepted Answer

Star Strider
Star Strider on 24 Jul 2016
This approach works:
M = randi(9, 20, 3); % Create Data
M(1:9,2) = ones(9,1)*3; % Create Data
M(10:end,2) = ones(11,1)*7; % Create Data
[U2,ia,ic] = unique(M(:,2)); % Unique Values In Column #2
rows = accumarray(ic, 1); % Lengths Uf Unique Values
Result = mat2cell(M, rows, size(M,2)); % Cell Array Of Separated Matrices

More Answers (1)

Azzi Abdelmalek
Azzi Abdelmalek on 24 Jul 2016
%------Example---------------
A(1:1000,[1 3])=randi(100,1000,2)
A(:,2)=randi(3,1000,1)
%-----The code-----------------
[ii,jj,kk]=unique(A(:,2))
out=accumarray(kk,(1:numel(kk))',[],@(x) {A(x,:)})

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