How do convert array x to array z?

Hi, How do convert array x to array z ?

x = [4 4 8 8 8 5 5 4 8 8 4]

Z = [1 1 2 2 2 3 3 1 2 2 1]

4 -> 1

8 -> 2

5 -> 3

Answer 1

[Stephen23]

If you want to convert the first value, whatever it may be, to 1, the second to 2, etc:

>> x = [4 4 8 8 8 5 5 4 8 8 4];
>> [~,ia,ic] = unique(x,'first');
>> [~,ia] = sort(ia);
>> z = ia(ic)
z =
   1   1   2   2   2   3   3   1   2   2   1

[Hamidreza Rafat]

Tanx

Answer 2

[Andrei Bobrov]

or just:

[~,~,z] = unique(x,'stable');

or more

[~,z] = ismember(x,[4 8 5]);