/* graphics */

library pgraph;

load path= c:\gausswin\x\boe\  xx4;

t = seqa(1,1,rows(xx4));
xy(t,xx4); waitc;

title("FT30 ");
xlabel("observation");
ylabel("FT30");
_ptek="ex7.tkf";
xy(t,xx4); waitc;

x = seqa(-2.5,0.2,26); y=x; rho = 0.5;
V = (1~rho)|(rho~1);
fxy = (1/(2*pi*(det(V)^0.5)))*exp(-0.5*(x.*x-2*rho*x*y'+ (y.*y)')/(1-rho^2));
surface(x',y,fxy);waitc;


xlabel("y");
ylabel("x");
_ptek="ex7a.tkf";
surface(x',y,fxy);