How to evaluate vector function defined in 2D with meshgrid?

Question

Yonghyeon Jeon 2021-9-19

回答： darova 2021-9-19

Hi, guys.

I would like to evaluate and get the function values of vector function defined in 2D.

For example, we assume that we have the function defined in 2D and discretized domain.

These are coded in matlab as follows:

fun = @(x, y) [sin(x) .* sin(x) ; cos(x) .* cos(y)];
xgrid = linspace(0, pi, 3);
ygrid = linspace(0, pi, 4);
[xmesh, ymesh] = meshgrid(xgrid, ygrid);

So, the result that I want is the 3-dimensional matrix such as

result(:,:,1) = [0, 1, 0 ; 0, 1, 0 ; 0, 1, 0 ; 0, 1, 0];
result(:,:,2) = [1, 0, -1 ; .5, 0, -.5 ; -.5, 0, .5 ; -1, 0, 1];

I tried

fun(xmesh, ymesh)

but it didn't give me the wanted result.

Plese give me a novel advises.

Answer 1

darova 2021-9-19

Try cat

fun = @(x, y) cat(3, sin(x).*sin(x), cos(x).*cos(y));