check if all elements are positive in matlab

To check if all elements in a matrix or array are positive, you can use logical indexing along with the "all" function in MATLAB. First, create a logical matrix where the elements are true if the corresponding element in the original matrix is positive, and false otherwise. Then, use the "all" function to check if all elements in the resulting logical matrix are true. Here's the code:

main.m
% Example matrix
A = [1 2 -3; 4 5 6; 7 -8 9];

% Create logical matrix
positives = A > 0;

% Check if all elements are positive
all_positive = all(positives(:));

% Display result
if all_positive
    disp("All elements are positive")
else
    disp("Not all elements are positive")
end
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This code will output "Not all elements are positive" since there is a negative element in the matrix. However, if all elements were positive, it would output "All elements are positive".