使用原始数据的饼图

Question

I have 4 types of objects with labels 1,2,3 and 4.

Now, I have N objects as a vector of Nx1 where each element corresponds to the class of the object.

So, if I have 5 objects, I might have a vector that looks like

D = [1,1,3,4,2]

What I want to do is the get a pie chart for the data D . A hotch-potch way of doing it is:

count_data = zeros(4,1);
for it=1:4
count_data(it) = sum(D==it);
end
pie(count_data)

Is there a clean way of doing this?

Answer 1

You can use histc to count occurences of integers (among other uses). Instead of your for-loop put count_data = histc(D, 1:4) .