functions to exclude repetitions

hello everyone, I want to know if there is a function that allows me, through a random variable, to run my code with all the elements of a matrix 1xn without repetition. here's an example of what i want to do:

Caos = [1:10];             %is my matrix
a = min(Caos);             %minimum value of "Caos"
b = max(Caos);             %maximum value of "Caos"
c = length(Caos);                                                            
d = 0;                     %counter
R = randi([a b],1);        %random variable that's I don't want to repeat
while d<c
    %execute my code
d=d+1
end

Answer 1

[per isakson]

Guess:

    R2 = unique( R, 'stable' );

'stable' to avoid to sort R2

[Nicolò]

ehm no, I want to keep the elements from array without the result's repetition. Like the balls with the numbers in lottery : you must take each time once until they finish.

[Matt Kindig]

It sounds like randperm() is what you want, then. This will randomly sort all of the integers between 1 and n, where n=10 in your example. You can then iterate through the elements of this vector, which by definition will not contain repeats (simulating your lottery-ball example).

doc randperm

[Nicolò]

randperm seems to be a good solution, i'll give it a shot.