Random numbers from array

Suppose I have the following array A=[2,1,5,6,20,55,6,9,100,1000,325,2301] which contains distinct numbers I want to select for example four elements from the array randomly and then delete them from the original array. For example if the selected numbers were 20,2,9,325 so the new array R=[20,2,9,325] and A=the remaining elements.

Answer 1

[Geoff Hayes]

Mohammed - just use randperm to generate four random numbers that you can use as indices into your array. Try the following

 % generate the four random indices
 randIdcs = randperm(length(A),4);

 % initialize R to be the four numbers of A
 R = A(randIdcs);

 % remove those four numbers from A
 A(randIdcs) = [];

If order is important, then just sort the output of randperm

 randIdcs = sort(randperm(length(A),4));

[Yasir Khan]

will these indices be unique?

[Walter Roberson]

The output of randperm() will be unique values.