# How to get a random vector whose elements arrangement is the same as that of my desired vector

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Sadiq Akbar on 30 Sep 2020
Commented: Sadiq Akbar on 2 Oct 2020
If I have a desired vector u=[3 1 5 105 155 50].
Now I want to genrate 10 random vectors of the same size as above u. Then I want to get one of those random vectors which is nearly equal to u and has the same arrangment of elements as that of my desired vector u.
i.e. if one of those generated vector is say for example [1.001 2.99 4.999 154.999 105.001 49.999]. This is nearly equal to my above desired vector u but the arrangement of elements of this vector is not the same as that of my u vector. So I want to get it in the same arrangement of elements as that of my u vector. How can we do this?
Sadiq Akbar on 1 Oct 2020
Dear madhan ravi, the page shows me that you have edited the answer 11 minutes agao, but I cann't see it. What should I do now to see your answer? Regards

madhan ravi on 30 Sep 2020
Edited: madhan ravi on 30 Sep 2020
Use the second output of sort() to the newly sorted generated vector as index.
[~, ix] = sort(u);
N = sort(newly_generated_vector);
Wanted = N(ix)
Sadiq Akbar on 2 Oct 2020
I am extremely SORRY madhan ravi. No, I don't play with you. Even I don't want to waste anybody's time. Neither I can think like that. Its one's preciuos time that one spares for me. So why would i want to do like that when you are sparing your precious time for me. Actually its my fauklt as I am not as expert as you are. If I were expert, then why would I asked for help. But due to my weakness, I was doing a serious mistake which is that the program which I was running was as follows:
% Help by sir madhan ravi from Mathworks
u1=[1 3 5 10 30 50]; % Desired vector 1
u2=[3 1 5 30 10 50]; % Desired vector 2
u3=[5 1 3 50 10 30]; % Desired vector 3
%%%%%%%%%%%%%%%%%%%
%1st Try of sir madhan ravi
%%%%%%%%%%%%%%%%%%%
% % % [~, ix] = sort(u2);
% % % N = sort(u3);
% % % Wanted = N(ix)
%%%%%%%%%%%%%%%%%%%%%%%%%
% 2nd Try of sir madhan ravi
%%%%%%%%%%%%%%%%%%%%%%%%
% [~, ix] = sort(u3);
% [U1, ix1(ix)] = sort(u1); % If u1 is my newly generated vector for example
% Wanted = U1(ix1) %-----------Correct
% % My Change in u
[~, ix] = sort(u1);
[U1, ix1(ix)] = sort(u2); % If u1 is my newly generated vector for example
Wanted = U1(ix1) % --------------Wrong
% [~, ix] = sort(u2);
% [U1, ix1(ix)] = sort(u3); % If u1 is my newly generated vector for example
% Wanted = U1(ix1) %---------------Wrong
%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% 3rd Try of sir madhan ravi
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
u1=[1 3 5 10 30 50]; % Desired vector 1
u2=[3 1 5 30 10 50]; % Desired vector 2
u3=[5 1 3 50 10 30]; % Desired vector 3
%%%%%%%%%%%%%%%%
% %1st check
%%%%%%%%%%%%%%%%%%
% [~, ix] = sort(u3);
% [~, ix1(ix)] = sort(u1);
% Wanted = u1(ix1);
% Check_1 = isequal(u3, Wanted)
%%%%%%%%%%%%%%%%%%%%%%%
%2nd check-----------------Wrong Result
%%%%%%%%%%%%%%%%%%%%%%%
[~, ix] = sort(u1);
[~, ix1(ix)] = sort(u2);
Wanted = u2(ix1);
Check_2 = isequal(u1, Wanted)
%%%%%%%%%%%%%%%%%%%%%%
% % 3rd Check
%%%%%%%%%%%%%%%%%%%%%%
% [~, ix] = sort(u2);
% [~, ix1(ix)] = sort(u3);
% Wanted = u3(ix1);
% Check_3 = isequal(u2, Wanted)
I didn't think that there was a semicolon at there end of the Wanted vector in your correct program.At the same time there was no semicolon at the end of the Wanted vector of the wrong program which was also running and was not commented by me. So its my fault and i am extremely sorry for that.
What should I do that your kind heart forgives me?

the cyclist on 30 Sep 2020
Edited: the cyclist on 30 Sep 2020
Do you want something like this, which adds some random "noise" around the elements of u?
u = [3 1 5 105 155 50];
m = 10;
n = size(u,2);
r = zeros(m,n);
for ii = 1:m
r(ii,:) = u + 0.001*(rand(1,n)-0.5);
end
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Sadiq Akbar on 30 Sep 2020
Thank you very much the cyclist for your prompt response also. I checked your program also. But I don't want like this. I want as I said to madhan ravi above.