Shifting position of an element in a vector from 1st to last

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i want to change the position of a number in element from 1st to last
for example if i have a sequence 1-2-3-4-5
first i want to move 1 to end of vector like 2-3-4-5-1
then i want to move 2 like 1-3-4-5-2
then 3, 1-2-4-5-3
and so on withoutchanging order of other.i can do it with for loop but is there a single command for this in Matlab??
  2 Comments
Jan
Jan on 14 Mar 2019
Edited: Jan on 14 Mar 2019
You want to get different outputs. Then it is not clear, what kind of "single command" you want for this job. It is not clear, what you want as output. But solving this with a for loop is easy, so why don't you use it?
Ayesha Maroof
Ayesha Maroof on 14 Mar 2019
Because i am lookig for a single command.
if 1-2-3-4-5 is the main sequence, i want all combinations like this:
2-3-4-5-1
1-3-4-5-2
1-2-4-5-3
1-2-3-5-4
like this.I want to move step by step elements to end without changing the main sequence

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Accepted Answer

Stephen23
Stephen23 on 14 Mar 2019
Here is a general solution for any sized vector (not in a single command though):
>> N = 5;
>> V = 1:N
V =
1 2 3 4 5
>> [~,X] = sort(eye(N),2);
>> M = V(X)
M =
2 3 4 5 1
1 3 4 5 2
1 2 4 5 3
1 2 3 5 4
1 2 3 4 5
  2 Comments
Ayesha Maroof
Ayesha Maroof on 16 Mar 2019
Thank you soooo much Stephen.anyway its better than using a for loop.
Jan
Jan on 16 Mar 2019
+1. When the vector is 1:N, the single command is working already:
[~,X] = sort(eye(N),2)

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More Answers (1)

Jan
Jan on 16 Mar 2019
Edited: Jan on 16 Mar 2019
Or:
X = [(1:N-1) + triu(ones(N, N-1)), (1:N).']
% Auto-expanding: >= R2016b
This is 2 times faster for N=200, and 3 times for N=400 than sorting the eye matrix, but less nice.

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