param0 = [1,1]; step = 0.01; m = 50; arange = linspace(0,1,m); brange = linspace(.5,1.5, m); [A,B] = meshgrid(arange, brange); E = 0*A; x = linspace(-5,5,20); y = .5*x + 1 + randn(1, length(x)); U = 0*A; V = 0*A; for i = 1:m for j = 1:m E(i,j) = lserr([A(i,j), B(i,j)], x, y); grad = lserr_gradient([A(i,j), B(i,j)], x, y); U(i,j) = grad(1); V(i,j) = grad(2); end end colormap('jet'); surf(A,B,E, 'FaceAlpha',.5);