cleaning duplicate data unique matlab2013

I have a matrix like the following. I tried to eliminate duplicate data on both sides with x1 as the primary key, wherein if x1 cleaned then x2 will be cleaned in the same position. using matlab 2013a I tried, but to no avail. is there any other way to eliminate the duplicate data. thank you

[Jan]

What does "x1 as the primary key" mean? Please explain "to no avail" with any detail.

[catur suharinto]

Dear Jan Simon Sorry for the unclear. I want to convert old matrix to new matrix.

Answer 1

[Rik]

I've seen a more efficient piece of code that can do this somewhere on this forum somewhere in past month or so, but I'm too lazy to look it up. So here is a solution that uses unique to find the indices and then uses a loop to fill y2.

x=[1 2  3  3  3  3  3  4  4  4  4  4 5 5];
y=[6 7 10 11 13 10 10 11 12 13 11 12 1 2];
x2=unique(x);
y2=zeros(size(x2));
for n=1:length(x2)
    y2(n)=mean(y(x==x2(n)));
end