Sorting a matrix from smallest to biggest left to right

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I made this code here for a matrix that was only 1 row. Now that I have matrices with multiple rows I don't know how to make it sort from left to right. Right now it sorts from top to bottom.
For example, the third matrix goes
4 7
5 8
6 9
I need it to go
4 5
6 7
8 9
m=numel(a);
for j=1:1:(m-1)
for i=1:1:(m-1)
if a(i)>a(i+1)
temp=a(i);
a(i)=a(i+1);
a(i+1)=temp;
end
end
end
These are some of the matrices I need to work with
a=[3 -2 1;4 0 5;1 2.2 -3]
a=[4 2 1;9 3 5]
a=[9 8;7 6;5 4]
Any help is appreciated. Thank you.

Answers (2)

Stephen23
Stephen23 on 15 Apr 2016
Edited: Stephen23 on 15 Apr 2016
The trick is to transpose, then use the columnwise element order:
>> M = [4,7;5,8;6,9]
M =
4 7
5 8
6 9
>> tmp = M.';
>> tmp(:) = sort(tmp(:));
>> out = tmp.'
out =
4 5
6 7
8 9
Basically what you are doing is simple, when you think in terms of columns, not rows.
  1 Comment
Vinny
Vinny on 15 Apr 2016
The only issue is I can't use built in functions like sort, so I need a way to have it do this in the loop.

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Andrei Bobrov
Andrei Bobrov on 15 Apr 2016
M = [4,7;5,8;6,9]
out = reshape(M,size(M,2),[])';
  1 Comment
Vinny
Vinny on 15 Apr 2016
I've integrated this into the loop and it works and gives me the matrix the way I want it.
for j=1:1:(m-1)
for i=1:1:(m-1)
if a(i)>a(i+1)
temp=a(i);
a(i)=a(i+1);
a(i+1)=temp;
out=reshape(a,size(a,2),[])';
end
end
end
But for this assignment I can't use built in functions like reshape. How can this be done as a loop?

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