function d = draw()
    rng = inline('1./(x.^2+1)')
    drng = inline('(-2*x)./((x.^2+1).^2)')

    xs = [-5:1:5];
    xss2 = [-5:0.1:4.9];
    xss = [-5:0.1:5];


    poly = polyinterp(xs, rng(xs), xss);
% piece = piecelinear(xs, rng(xs), xss2);
    hrm = hermite(xs, rng(xs), drng(xs), xss);

% xss, poly, 'y', xs, rng(xs), 'or',  xss2, piece, 'g',
    plot(xss, hrm, 'b')
end