Automatically set number of outputs of the gradient function

I have a loss function I define to minimize some gradient magnitude. However, the dimension of my input data will change so I want to make my gradient have a generalized output. I have something close to a solution but Dont know how to get rid of the hard coded 2nd line below.

grad_vec = zeros([size(DATA),numel(size(DATA))]);
[grad_vec(:,:,:,1),grad_vec(:,:,:,2),grad_vec(:,:,:,3)] = gradient(DATA);
grad_mag = (sum(abs(grad_vec).^n,numel(size(DATA)))).^(1/n);

[tiwwexx]

I do know one solution but it would be rather ugly

if numel(size(DATA))==2
    [grad_vec(:,1),grad_vec(:,2)] = gradient(DATA);
elseif numel(size(DATA))==3
    [grad_vec(:,:,:,1),grad_vec(:,:,:,2),grad_vec(:,:,:,3)] = gradient(DATA);
elseif numel(size(DATA))==4
    [grad_vec(:,:,:,:,1),grad_vec(:,:,:,:,2),grad_vec(:,:,:,:,3),grad_vec(:,:,:,:,4)] = gradient(DATA);
.
.
.

end

Then I know that my data will have no more than say 10 dimensions so I just continue this elseif to the 10th case

[Bruno Luong]

it probably miss a second colon on lhs

if numel(size(DATA))==2
    [grad_vec(:,:,1),grad_vec(:,:,2)] = gradient(DATA);
...

[Stephen23]

The solution is explained here:

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them

Answer 1

[Bruno Luong]

A = rand(10,10,10);

% This works for any dimensions of A
if isvector(A) % EDIT
    N = 1;
else
    N = ndims(A); % 3 in this example
end
G = cell(1,N);
[G{:}] = gradient(A);
G = cat(N+1,G{:});

size(G)

ans = 1×4

10 10 10 3

p = 2; % whatever power in >=1
Gmag = sum(abs(G).^p,N+1).^(1/p);
size(Gmag)

ans = 1×3

10 10 10

[tiwwexx]

Good solution and I appriciate the answer!

[Bruno Luong]

Not only it's good but it's also correct.

FYI you accept an answer from @Star Strider that is not correct (it ignores all the partial derivatives wrt to dimension > 1)

[tiwwexx]

Good catch