f=[a=2,k−=−4,k+=7,t=5] the number of positive normalized elements in the system is in matlab

You can use the following code to count the number of positive normalized elements in the given array:

main.m
f = [2, -4, 7, 5];
f_norm = f./norm(f,1);
num_pos_norm = sum(f_norm > 0);
disp(num_pos_norm);
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Here, we first calculate the L1-norm of the array using norm(f,1) function. Then, we divide each element of the array by the L1-norm to get the normalized array f_norm. Finally, we count the number of elements in f_norm that are greater than 0 using sum(f_norm > 0) function.

Note that the array f in the given question is not in valid matlab syntax, so I assumed it to be [2, -4, 7, 5].