% Show Epanechnikov, Biquadratic, Gaussian, Cubic kernels.

tc=-1:0.001:1;
b=0;
tg=-4:0.01:4;

ge=(3./4).*((1-tc.^2));
gg=(1./(2.*pi).^(1/2)).*(exp(-(0.5).*((tg).^2)));
gc=(35./32).*((1-(3.*tc.^2))+3.*tc.^4-tc.^6);
gb=(15./16).*((1-(2.*tc.^2))+tc.^4);

subplot(221);
plot(tc,ge,'b');
axis([-1 1 0 0.8]);
title('Epanechnikov kernel');
grid;


subplot(222);
plot(tc,gb,'b');
axis([-1 1 0 1]);
title('Biquadratic kernel');
grid;%axis('off')

subplot(224);
plot(tg,gg,'b');
axis([-4 4 -0 0.45]);
grid;
title('Gaussian kernel');%axis('off')

subplot(223);
plot(tc,gc,'b');
axis([-1 1 0 1.2]);
title('Cubic kernel');
grid;%axis('off')


% "Complex and Chaotic Nonlinear Dynamics. 
% Advances in Economics and Finance, 
% Mathematics and Statistics" 
% T.Vialar, Springer 2009.
% Copyright(c) 