clear; 
clc;
E = dlmread('data.txt');
x = E(:,1);
y = E(:,2);
q = [1; .25; .25];
function res = f(x,q)
  res = q(1) - exp((q(2).*x).^q(3));
end
[fr,q,cvg,iter_r] = leasqr(x,y,q,'f',.0001,40);
plot(x,y)