MATLAB: How to operate on 2d matrices in a 3D array

MATLABmatrix manipulation

Hi,

I have a set of n 3×3 matricies orgenized in a 3D array with dimesions 3x3xn.

I want to operate on all 3×3 matricies: I want to get a vector of determinants and a vector of trace of each 3×3 matrix.

I also want to calculate a 3x3xn array which will hold the 3×3 inverse of each matix.

I can do it using a for loop, of couse, calculating in each iteration for the ith matrix.

Is there a simpler and faster way to do it?

Thanks,

Alon

Best Answer

data = randi([1,10], 3,3,4);    % your matrix with n = 4
data_det = arrayfun(@(i)det(data(:,:,i)), 1:size(data,3));    
data_trace = arrayfun(@(i)trace(data(:,:,i)), 1:size(data,3));
data_inv = arrayfun(@(i)inv(data(:,:,i)), 1:size(data,3), 'UniformOutput', false);

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