Generate X and Y matrices for three-dimensional plots

Syntax：
[X,Y] = meshgrid(x,y)
[X,Y] = meshgrid(x)
[X,Y,Z] = meshgrid(x,y,z)

Description：

[X,Y] = meshgrid(x,y) transforms the domain specified by vectors x and y into arrays X and Y, which can be used to evaluate functions of two variables and three-dimensional mesh/surface plots. The rows of the output array X are copies of the vector x; columns of the output array Y are copies of the vector y.
[X,Y] = meshgrid(x) is the same as [X,Y] = meshgrid(x,x).
[X,Y,Z] = meshgrid(x,y,z) produces three-dimensional arrays used to evaluate functions of three variables and three-dimensional volumetric plots.

 
Remarks：

The meshgrid function is similar to ndgrid except that the order of the first two input and output arguments is switched. That is, the statement [X,Y,Z] = meshgrid(x,y,z)

produces the same result as [Y,X,Z] = ndgrid(y,x,z)

Because of this, meshgrid is better suited to problems in two- or three-dimensional Cartesian space, while ndgrid is better suited to multidimensional problems that aren\'t spatially based.
meshgrid is limited to two- or three-dimensional Cartesian space.

From：网易博客

详细解释：help meshgrid

meshgrid用于从数组a和b产生网格。生成的网格矩阵A和B大小是相同的。它也可以是更高维的。

[A,B]=Meshgrid(a,b)
生成size(b)Xsize(a)大小的矩阵A和B。它相当于a从一行重复增加到size(b)行，把b转置成一列再重复增加到size(a)列。因此命令等效于：

A=ones(size(b))*a;
B=b\'*ones(size(a))

如下所示：

>> a=[1:2]

a =

     1     2

>> b=[3:5]

b =

     3     4     5

>> [A,B]=meshgrid(a,b)

A =

     1     2
     1     2
     1     2

B =

     3     3
     4     4
     5     5

>> [B,A]=meshgrid(b,a)

B =

     3     4     5
     3     4     5

A =

     1     1     1
     2     2     2