how to calculate the positive element in the system in matlab

You can calculate the positive elements in a MATLAB array by using logical indexing.

Here is an example code snippet that demonstrates how to do that:

main.m
A = [-1 2 3 -4 5]; % example array
positive_elems = A(A > 0); % select only positive elements
num_positive_elems = length(positive_elems); % count how many positive elements there are
disp(num_positive_elems);
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5 lines

The first line creates an array for demonstration purposes. The second line uses logical indexing to select only the positive elements and store them in a new array called positive_elems.

The third line calculates the number of positive elements in positive_elems using the length() function, and stores the result in a new variable called num_positive_elems. The fourth line displays the result using the disp() function.