how to remove duplicate matrixes in a cell array?

Question

I have a cell matrix TILER that include some matrix with different sizes.

TILER=[22x4 double]    [1265x4 double]    [58x4 double]    [31x4 double]     [58x4 double]

and we know that some matrixes are duplicate, for example [58x4 double] matrix. how can we remove duplicate matrixes from a cell array to have :

TILER=[22x4 double]    [1265x4 double]    [58x4 double]    [31x4 double]

here is a link, but it doesn't work

Answer 1

In this case it's hard to avoid loops. You can go along the following lines:

ind = true(1,numel(TILER)); %// true indicates non-duplicate. Initiallization
for ii = 1:numel(TILER)-1
    for jj = ii+1:numel(TILER)
        if isequal(TILER{ii}, TILER{jj})
            ind(jj) = false; %// mark as duplicate
        end
    end
end
TILER2 = TILER(ind);

Some optimizations are possible. For example:

• In the inner loop don't consider values that have been detected as duplicates in a previous iteration of the outer loop.
• Do a first check for equality of matrix sizes (this can be done efficiently with bsxfun), and then only test for equality between matrices that have the same size.