How to compute percentile share of character values in column vector in a for loop?

Hello,

I have a column vector 'Colour' that can take on values like ‚Brown‘, ‚Blonde‘ and ‚Black‘ in a bigger matrix of characteristics. I want it to only look at these observations in a larger loop for 'Test' if they have a share above 75% in the vector. So far I used this method:

for n = 1: length(Test.Colour)
            if sum(Test.Colour(:) == Test.Colour(n))./numel(Test.Colour).*100 >= 75; 
            Test = Test(Test.Colour == Test.Colour(n,:));
            else Test = NaN 
            end       
            end

but I get the error ‘Dot indexing is not supported for variables of this type’. Does anyone know how to go around solving this?

[Rik]

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