## how can I create a vector with unknown length?

### sapir (view profile)

on 9 May 2013

I need to create a user defined function that recieves a vector x of any length and than sorts the vector from the largest to the smallest into a new vector y. I'm not allowed to use the function sort. I have no idea how to begin! please help me!! thank u!!!

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### Roger Stafford (view profile)

on 9 May 2013

` https://en.wikipedia.org/wiki/Sorting_algorithm`

I tend to prefer the merge sort algorithm.

### John Doe (view profile)

on 9 May 2013
Edited by John Doe

### John Doe (view profile)

on 9 May 2013

The most intuitive (and simple to implement) is probably bubble sort:

https://en.wikipedia.org/wiki/Bubble_sort

Since this is an assignment, I'll leave some of it open, so fill in the blanks =)

```n=length(A);
```
```for j=1:1:n-1
% comparing each number with the next and swapping
for i=1:1:n-1
if ...
% In here you should check if A(i) > A(i+1)
% If so, switch places. You need a temporary
% variable, in order to not overwrite something.
end
end
end
```

Good luck =)

### Sean de Wolski (view profile)

on 9 May 2013

```xsorted = sortrows(x(:),-1)
```

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