x=randn(1,20);
y=x'*x;
domain = [-3:0.2:3];
range = [-5:0.2:5];
[x,y] = meshgrid(domain,domain);
r = sqrt(x.^2 + y.^2) + 0.00001;
z = sin(pi*r)./(pi*r);

t = range;
s = sinc(t);
s2 = s'*s;

S = fft(log(t));
title('plot(fft(log(t)))');
plot(S)
clg
pause(.1)

t = 0.1:0.1:100;
title('polar(t,t.*log(t))');
polar(t,t.*log(t))
clg
pause(.1)

% gsplot is another useful plotting routine:
title('using gsplot');
gsplot rand (5, 2)
clg
pause(.1)

z = [0:0.05:5];
title('using plot3');
plot3(cos(2*pi*z), sin(2*pi*z), z, ";helix;");
clg
pause(.1)

[x,y] = meshgrid([-2:.2:2]);
Z = x.*exp(-x.^2-y.^2);
title('using surf');
surf(x,y,Z,gradient(Z))
clg
pause(.1)
     
function [y1,y2] = test(x)
y1 = x + 4
title('test');
hold("on"); ## new line !
plot(y1,'1')
y2 = 2*x.^2 + 3*x + 2
plot(y2,'2')
hold off
clg
pause(.1)
endfunction

test([0:.1:3])

x=randn(1,20);
title('Messy Random Data grid, without sine');
mesh(x'*x)

title('Messy Random Data grid, with sine of same');
hold("on") % plots the next surface on top of the old one:
x=sin(x);
mesh(x'*x)
hold off