Determining the number of occurrences of each unique element in a vector

Question

How can I determine the relative frequency of a value in a MATLAB vector?

vector = [ 2 2 2 2 1 1 1 2 2 1 1 1 2 2 2 2 1 2 ];

What function w

Answer 1

For the most general case where you have a vector of floating point values, you can use the functions UNIQUE and ACCUMARRAY:

[uniqueValues,~,uniqueIndex] = unique(vector);
frequency = accumarray(uniqueIndex(:),1)./numel(vector);