can you fix this matrix?

m=ones(4);
x=-1;
for i=1:3;
m(1,1)=-x;
m(1,1+i)=x;
m(2:end,1:end)=x;
end

i want to make it's shorter and easier. can you fix it?

example:

[1 1 1 1
1 1 1 1
1 1 1 1
1 1 1 1]

i want the output will be

[1 -1 -1 -1
-1 -1 -1 -1
-1 -1 -1 -1
-1 -1 -1 -1]

thank you very much

[Walter Roberson]

Why are you re-assigning m(1,1) during each iteration of the "for" loop?

Answer 1

[Walter Roberson]

m = -ones(4);
m(1,1) = 1;

[Tia]

it works.. thank you