Steepest Descent Method COde

I wrote a code on Steepest Decsent Method, with 550 X 550 random number matrix

M=rand(550);

P=0.5*(M+M');

N= sum(P,2);

D=abs(diag(P));

W=N-D;

A = P - diag(diag(P)) + diag(W);

X=(1:550)';

b=A*X;

x=zeros(550,1);

t=1e-7;

res=1;

count=1;

i=1;

while res>t

r=b-A*x;

p=r'*r/(r'*A*r);

x=x+p*r;

res(i)=norm(r);

i=i+1;

end

Someone please tell me if it is correct it or not ?

[Walter Roberson]

Steepest descent implies that you have a function being evaluated, but it is not clear what the function is. Something about eigenvalues? eigenvalues of a random matrix??