FUNCTION shift of vector's position

ANYONE CAN HELP ME PLS TO CREAT THIS FUNCTION I TRIED TO DO IT BUT I COULDNT WITHOUT any toolbox functions of cycles

function rotated = rotateRight( vector, shift )
% Performs cyclic shift of vector's position - the ROR operation.
% Performs horizontal ROR, if a matrix is supplied, rotate all rows.
% The scalar shift specifies how many positions to rotate
%	if negative, a ROL operation is performed.
% You cannot use any toolbox functions of cycles,
% just indexing.

Answer 1

[amjad hammad]

rotated = zeros(1, size(vector, 2))
shift = mod(shift, size(vector, 2))
rotated(1:shift) = vector(end-shift+1:end)
rotated(shift+1:end) = vector(1:end-shift) 

i did it in this way but is there anyone have another method how to do it with same conditionals

[Walter Roberson]

This will work in one direction but not the other:

rotation([shift+1:end, 1:shift]) = vector

[amjad hammad]

thank you it work perfect

Answer 2

[Chunru]

Here is some pseudo code:

%1.  Let the vector index be idx = (0:n-1) + 1
%2.  When rotating to right by "shift" (which can be +ve/-ve), the corresponding index becomes
%       newIdx = mod((0:n-1) + shift, n) + 1;
%    where mod implements the rotation.
%3.  Get the rotated vector: y = vector(newIdx)

[amjad hammad]

thanks but i tried what you mean but i get this answer

y =

3 4 5 6 7 8 9 10 1 2

what i need be like this the and will be like arraythis vector 1:10 and shift 2

rotated =

9 10 1 2 3 4 5 6 7 8

[Chunru]

Then

newIdx = mod((0:n-1) - shift, n) + 1;

Answer 3

[Walter Roberson]

Take a copy of what is about to be overwriten.

Use array subscripts to move the old data to the new positions. For example

A(:,1:5) = A(:,3:7);

Now write the saved data to the other end of the array, into the spots vacated, like A(:,6:7)