% We can draw from predefined primitives
% and assemble the pieces into one drawing.
[x,y,z] = sphere(10);
mesh(x,y,z)
[x,y,z] = cylinder(30);
hold on
mesh(x,y,z)
% The argument of the cylinder is by default
% the radius and the axis of the cylinder is
% by default the z-axis.
% To make the cylinder taller, we multiply the
% z-coordinates by 30
z1 = 30*z;
figure
mesh(x,y,z1)
hold on
mesh(x,y,z)
% to flip the axis of orientation,
% we interchange z with x or y
mesh(x,z1,y)
% we can shift the axis
mesh(x,z1+15,y)
% the previous command heightened,
% to shift the axis, try y + 15:
mesh(x,z1,y+15)
mesh(1+x1,y1,z1)
hold on
mesh(x,y,z)
mesh(x1,y1,1+z1)
% we can make curve walls 
% For example, we can use a parabola
% y = x^2 as the wall.
t = 0:0.01:1;
p = t.^2;
figure
[x,y,z] = cylinder(p);
mesh(x,y,z)
q = sqrt(t);
[x,y,z] = cylinder(q);
hold on
mesh(x,y,z);
%
% We are going to make a script
% to model with splines
help spline
  defines a profile

usespline
figure
usespline
clf
usespline
usespline
usespline
usespline
usespline
diary off