%% why is meshgrid used?
x = 1:3
y = 1:3
x+y

[a b] = meshgrid(x,y);
a+b

z=1:3
x+y+z

[a b c] = meshgrid(x,y,z);
v=a+b+c

%% Examples:
x = linspace(-10,10,100);
y = linspace(-10,10,100);
[a b] = meshgrid(x,y);
surf(a,b,exp(-(a^.2+b^.2)));
axis([-2 2 -2 2]);

z = linspace(-10,10,100);
[a b c] = meshgrid(x,y,z);
isosurface(a,b,c,exp(-(a.^2+b.^2+c.^2)),.5);
axis([-2 2 -2 2 -2 2]);
lighting phong;

%% Is there another way to get a 3D array?
x=1:3;
y=1:3;
z=1:3;
v = zeros(length(x), length(y), length(z));
for i=1:3
   for j=1:3
      for k=1:3
         v(i,j,k) = x(i)+y(j)+z(k);
      end
   end
end


%% String concatenation
[1 2 3]  % a vector of three elements

['1' '2' '3'] % a vector of three elements that looks like 123

[['1' '2' '3'] ['4' '5' '6']]  % looks like 123456

[[['1' '2' '3'] ['4' '5' '6']] ['7' '8' '9']]  % looks like 123456789

[[['1' '2' '3'] ['4' '5' '6']] [['7' '8' '9'] ['a' 'b' 'c']]]  % a vector