用空[]替换单元格的重复值-MATLAB

Question

So I have a 1x348 cell composed of numbers and empty brackets. Ie ... [] [] [] [169] [170] [170] [170] [171] [172] [] []... All what I want to do is change the repeated numbers to empty brackets []. I need to hold the places. I tried this, but am not having any success. It is also not ideal, because in the case with more than one repeat, it would just replace every other repeat with [].

for jj = 1:length(testcell);
    if testcell{jj} == testcell{jj-1}
        testcell{jj} = []
    end

Any help would be greatly appreciated :-)

Answer 1

The only thing your code lacks is some variable to store current value:

current = testcell{1};
for jj = 2:length(testcell)
    if testcell{jj} == current
        testcell{jj} = [];
    else
        current = testcell{jj};
    end
end

But it's better to use Daniel's solution =).

Answer 2

Lets assume you have {1,1,1} . First iteration will change this to {1,[],1} and second iteration does not see any repetition. Thus iterating backwards is probably the easiest solution:

for jj = length(testcell):-1:2
    if testcell{jj} == testcell{jj-1}
        testcell{jj} = [];
    end
end

Then the first step will result in {1,1,[]} and the second in {1,[],[]}

Answer 3

Alternatively, you could use NaN values to represent cells with empty matrices, and vectorize your code:

testcell(cellfun('isempty', testcell)) = {NaN};
[U, iu] = unique([testcell{end:-1:1}]);
testcell(setdiff(1:numel(testcell), numel(testcell) - iu + 1)) = {NaN};
testcell(cellfun(@isnan, testcell)) = {[]};