could anyone help me how to solve the issue in the following code

code:

unused_rows1=1:12;
while ~isempty(unused_rows1)
rows1_matrix=reshape(unused_rows1,[],2);
rows1_matrix(:,end)=rows1_matrix(end:-1:1,end);
for k=1:size(rows1_matrix,1)
    rows1=rows1_matrix(k,:)
    y=diff(rows1)
    unused_rows1=[];
end
end
z=max(y)

in this code i want to find the maximum of y.when i run the code i am getting 6 different values for y.

Among the 6 values i want to maximum value.Could anyone please help me on this.

Answer 1

[KSSV]

unused_rows1=1:12;
while ~isempty(unused_rows1)
rows1_matrix=reshape(unused_rows1,[],2);
rows1_matrix(:,end)=rows1_matrix(end:-1:1,end);
for k=1:size(rows1_matrix,1)
    rows1=rows1_matrix(k,:)
    y=diff(rows1)
    y_max = max(y) ; 
    unused_rows1=[];
end
end
z=max(y)

Answer 2

[per isakson]

Replace

y=diff(rows1)

by

y(k)=diff(rows1)