unique occurance table from array

I would like to be able to return the count of occurences of each element in a vector.

For example if I have a vector:

   x=[10 25 4 10 9 4 4]
I expect the result to be

10 2

25 1

4 3

9 1

Answer 1

[Star Strider]

Use the hist function:

x=[10 25 4 10 9 4 4];
ux = unique(x);

counts = hist(x, ux);
result = [ux' counts']

[Rahul Shelar]

Thanks its really working using hist function on octave..... I didnt knew about hist function I ve tried like this y=unique(x); disp(y); m=length(y); n=length(x); disp(n);

a=zeros(m);

for i=1:1:m

        for j=1:1:n

        if(y(i)==x(j))

              a(i)=a(i)+1;

        end

           end

        end

a=a(:,1); disp(a);

I really like ur approach.......

[Star Strider]

My pleasure!

[Image Analyst]

Also learn about its friends like histc() and imhist(). The histogram is like the PDF (probability distribution function), and related to that is the CDF, cumulative distribution function which you can get from passing the counts into cumsum(). By the way, hist() is now deprecated - they tell you to use histogram() instead.

[Star Strider]

Note that Rahul Shelar is using Octave.