Selection with no direct repeatition

Hello everyone,

I want to create 10 vectors with the following conditions:

Element number (i) is not equal to element number (i+1) and they have to be selected from set "a".

Length of each vector is 10 elements.

I am new to programming and I'd appreciate it if you can help me.

Here is me attempt:

%------------------------------------------------------------------------%
clear variables; 
close all;
clc;
%------------------------------------------------------------------------%

%% variables definition
n=10;
a=[0 4/3 2];
n1=nan;
%------------------------------------------------------------------------%

%% memory allocation
%------------------------------------------------------------------------%
i1=zeros(1,n);
i2=zeros(1,n);
n1=zeros(1,n);
n2=zeros(1,n);
%------------------------------------------------------------------------%

%% selection process
for i=1:n
i1(i) = randi(length(a));
n1(i) = a(i1(i));
i2(i) = randi((length(a)-1)); % to provide better selection ( picking from 2 element instead of 3)
i2(i) = i2(i) + (i2(i) >= i1(i));    
n2(i) = a(i2(i));
while (n1==n2)
n2(i) = a(i2(i));
end
n1=n2;
end
n2

Answer 1

[Hamzah Faraj]

idxr = randi(length(a),1,10); %// create the first batch of numbers
idx = diff(idxr)==0; %// logical array, where 1s denote repetitions for first batch
while nnz(idx)~=0
    idx = diff(idxr)==0; %// logical array, where 1s denote repetitions for
                      %// subsequent batches
    rN = randi(length(a),1,nnz(idx)); %// new set of random integers to be placed
                             %// at the positions where repetitions have occured
    idxr(find(idx)+1) = rN; %// place ramdom integers at their respective positions
end
r=a(idxr);
end

Answer 2

[Ameer Hamza]

See randperm(): https://www.mathworks.com/help/releases/R2020a/matlab/ref/randperm.html

>> randperm(10)
ans =
     2     3     9     7     5     8    10     6     4     1

[Hamzah Faraj]

hello Amer,

Thank you for your attempt to answer the question. However, this is not the right answer as this generates random numbers, but not from set a in the question.