how can i swap the matrix element using control statements or any built in functions?

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dani elias on 22 Nov 2020
Commented: Ameer Hamza on 25 Nov 2020
i have a square matrix m*n, (256*256). i am looking for functions (forward and reverse) to swaps elements until the bottom-right corner remain with lower values than any other part of the matrix, and and the top-left corner with high values. example
A=[6 5;4 7] become B=[7 6;5 4]; or D=[10 20 50 60;33 55 44 100; 3 6 12 9;4 2 1 3] become E=[100 60 55 50; 44 33 20 12;10 9 6 4;3 3 2 1];
here are sample of the code I design which does not provide the answer as i needed when i applied to 256*256 matrix.
a= [6 5;4 7];
[ b ] = swaps( a );
disp(b);
function [ b ] = swaps( a )
[m,n]=size(a);
for i=1:m
for j=1:n
temp=zeros();
if a([i,j]) >= a([i,j+1])
a([i,j])=a([i,j]);
else
temp(i,j)=a(i,j);
a(i,j)=a(i,j+1);
a(i,j+1)=temp(i,j);
if a([i,j+1]) >= a([i,j+1])
a([i,j+1])=a([i,j+1]);
else
temp([i,j+1])=a([i,j+1]);
a([i,j+1])=a([i+1,j+1]);
a([i+1,j+1])=temp([i,j+1]);
end
end
end
end
i thought the same method used to access element in other programming language could be applicable in MATLAB, by referencing the element in terms of (i,j) and encrements when needed.
Can any one help me on that?

Ameer Hamza on 22 Nov 2020
Edited: Ameer Hamza on 22 Nov 2020
You can just use sort() with reshape()
D = [10 20 50 60;33 55 44 100; 3 6 12 9;4 2 1 3]
E = reshape(sort(D(:), 'descend'), size(D)).'
Result
>> E
E =
100 60 55 50
44 33 20 12
10 9 6 4
3 3 2 1
Ameer Hamza on 25 Nov 2020
I am glad to be of help!