Help with basic code, pls

Hi everyone, I need to write a code that do as follow:

1.      Calculate the average of vectors a1,a2 (they are at the some size)
2.  Calculate the difference between the averages (|<a1> -<a2>|)
3.  Build a1-a2 matrix (Nx2)
4.  Randomly pick N numbers from the matrix to one column and the others to the second 
calculate the average and the difference again 
5.  Shuffle and repeat for 1000 times 
6.  Check if what we got in step 2 is within the higher 5% 
7.  If the answer is yes write: '1' otherwise '0'.

I attach the code i wrote and needs help to continue.

function [logic] = calc(a1,a2)
% a1,a2 are column vetors
mean_a1 =  mean(a1);
mean_a2 = mean(a2);
avg_diff = abs(mean_a1-mean_a2);
matrix = [a1,a2]; 
end

Thank you very much!

[madhan ravi]

post an example of your desired output

[Nushi Twelve]

for example if the result is true: logic = 1 ,else logic = 0.

Answer 1

[HilaN]

try randperm.

for i=1:1000

p = randperm(2 * size);

martix = [ rowmatrix(p(1:size)), rowmatrix(p(size+1:end)) ];

mean_row1 = mean(martix(1,:));

mean_row2 = mean(martix(2,:));

avg_diff_matrix(i) = abs(mean_row1-mean_row2);

end

[Nushi Twelve]

Thanks!

Answer 2

[TADA]

n = length(a1);
allItems = [a1(:);a2(:)];

% this line of code chooses n random numbers from your two vectors
rearranged = sortrows([allItems, rand(n*2, 1)], 2);
b1 = rearranged(1:n, 1);
b2 = rearranged(n+1:end, 1);

[TADA]

If in this assignment you MUST use an Nx2 matrix you can always randomize the order of the matrix linear indices instead of the vector itself...

n = length(a1);
allItems = [a1(:),a2(:)];

 % these are the linear indices of the matrix allItems
indices = 1:2*n;

 % this randomizes the indices and chooses n random items
rearrangedIndices = sortrows([indices(:), rand(n*2, 1)], 2);
b1 = allItems(rearrangedIndices(1:n,1));
b2 = allItems(rearrangedIndices(n+1:end,1));