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matlabmatrixpartition-problem

Matlab matrix partitioning

I would like to partition a matrix by an approximate even amount of rows. For example, if I have a matrix by these dimensions 155 x 1000, how can I partition it by 10 where each new matrix has the approximate dimensions 15 X 1000?

Solution

  • How about this:

    inMatrix = rand(155, 1000);
numRows  = size(inMatrix, 1);
numParts = 10;

a = floor(numRows/numParts);          % = 15
b = rem(numRows, numParts);           % = 5
partition = ones(1, numParts)*a;      % = [15 15 15 15 15 15 15 15 15 15]
partition(1:b) = partition(1:b)+1;    % = [16 16 16 16 16 15 15 15 15 15]
disp(sum(partition))                  % = 155

% Split matrix rows into partition, storing result in a cell array
outMatrices = mat2cell(inMatrix, partition, 1000)

outMatrices = 
[16x1000 double]
[16x1000 double]
[16x1000 double]
[16x1000 double]
[16x1000 double]
[15x1000 double]
[15x1000 double]
[15x1000 double]
[15x1000 double]
[15x1000 double]