Remove repeating values from vectors

I have two vectors, r and c, which have repeating patterns in them. c repeats the same number 3 times and then increases by 4, and repeats. r has three increasing numbers, and those three increasing numbers are repeated 3 times. The vectors are seen below. How do I remove repeating values in each? The resulting vectors should be c = [670; 674; 678] and r = [649; 652; 655].

c = [670; 670; 670; 674; 674; 674; 678; 678; 678];
r = [649; 652; 655; 649; 652; 655; 649; 652; 655];

Answer 1

[Jan]

c = [670; 670; 670; 674; 674; 674; 678; 678; 678];
r = [649; 652; 655; 649; 652; 655; 649; 652; 655];
c = unique(c, 'stable');
r = unique(r, 'stable');

Why do you ask for 2 vectors? Whould the pattern in one vector be considered in the other one? Or are they independent from each other?

Can the same value appear at multiple locations, but should be accepted then? In other words, what is the wanted output for:

v = [1, 1, 2, 2, 2, 1]

? If it is [1,2,1], you can use the fast https://www.mathworks.com/matlabcentral/fileexchange/41813-runlength:

v = RunLength(v);

Or:

function x = NonRep(x)
if ~isempty(x)
  x = x([true; diff(x(:)) ~= 0]);
end
end

c = NonRep(c);

[Andrew Poissant]

For the purposes of my work I need two separate vectors. Your answer did the trick, thanks!