Nan Mihai - Metode numerice

function x = eliminareGausianaPP(A,b)
n = size(A,1);
A = [A,b];
for i = 1:n-1
    p = i;
    for j = i+1:n
        if abs(A(j,i)) > abs(A(i,i))
            U = A(i,:);
            A(i,:) = A(j,:);
            A(j,:) = U;
        endif
    endfor
    while A(p,i)== 0 & p <= n
        p = p+1;
    endwhile
    if p == n+1
        disp('Nu are solutie unica!');
        break
    else
        if p ~= i
            T = A(i,:);
            A(i,:) = A(p,:);
            A(p,:) = T;
        endif
    endif

    for j = i+1:n
        m = A(j,i)/A(i,i);
        for k = i+1:n+1
            A(j,k) = A(j,k) - m*A(i,k);
        endfor
    endfor
endfor

if A(n,n) == 0
    disp('Nu are solutie unica!');
    return
endif

x(n) = A(n,n+1)/A(n,n);
for i = n - 1:-1:1
    sumax = 0;
    for j = i+1:n
        sumax = sumax + A(i,j)*x(j);
    endfor
    x(i) = (A(i,n+1) - sumax)/A(i,i);
endfor

endfunction