Matlab中有一个function来创建矩阵，其中每个元素是相同的矩阵索引的function？

Question

For example, a matrix where each value at row r and column c is

a=[r^2+c^2]

like a=[1, 4; 4; 18] a=[1, 4; 4; 18]

or

A=[F(r,c)]

A=[F(1,1) F(1,2) F(1,3);
   F(2,1) F(2,2) F(2,3);
   F(3,1) F(3,2) F(3,3)]

or

A(r,c)=F(r,c)

Answer 1

Mehtod 1

You can do it manually. First, create two matrices for rows and columns indices (suppose the matrix is nxm ):

R = repmat((1:n).',[1, m]); 
C = repmat((1:m),[n, 1]);

Then, write the function base on these two:

result = R.^2 + C.^2; % F(x,y) = x^2 + y^2

Or define the function inline and apply it on those two:

F = @(x,y)(x.^2 + y.^2);
result = F(R,C);

Mehtod 2

By @Cris Luengo, you can do it the first part by the meshgird function as well. Hence, we can generate R and C like the following:

[C,R] = meshgrid(1:n, 1:m)