MN_lab3_gauss

A=[3,1,-1;-1,5,-1;2,4,8]
b=[6;10;2]
wynik=A\b
[x,Ur] = f_gauss(A,b)


function [x,Ur]=f_gauss(A,b)
[n,m]=size(A);
x = zeros(n,1);
if (n~=m) error('Macierz A musi byc kwadratowa'); end
    Ur = [A,b];
  for k=1:(n-1)
  if A(k,k)==0
  error;
  end
  for jj=k+1:(n+1)
  for ii=k+1:n
 Ur(ii,jj)=Ur(ii,jj)-Ur(ii,k)*Ur(k,jj)/Ur(k,k);
end
end
end
%x=0;
for ii=n:-1:1
S=0;
for jj=ii+1:n
S=S+Ur(ii,jj)*x(jj);
end
x(ii)=(Ur(ii,n+1)-S)/Ur(ii,ii)
end
end