The usage of [~,I]=min(abs(A+B)) on a specific example

% Dear Users,
% I have a curve whose axes are defined as below:
u=[1.01 1.02 1.03 1.11 1.13 1.04 0.84 0.86 0.97 0.97]; % y-axis
t=[1 2 3 4 5 6 7 8 9 10];  %x-axis
uref=1;
umin=uref*0.90;
umax=uref*1.10;
% t= 1, 2, 3, 6, 9 and 10 --> for  let's say 6 seconds, the u values are within the limit (0.90 (umin)<=u<=1.10(umax))
% t= 4, 5, 7 and 8 --> for 4 seconds, the u values are out of  the limit
% Using the function of  [~,I]=min(abs(A+B))  or [~,I]=min(abs(A-B)), how can I calculate t_total=4 seconds (out of limit time)?
% Thanks in advance!

Answer 1

[Stephen23]

I don't really see how min can help you. Basic logical indexing would be simpler, e.g.:

>> nnz(u<umin | u>umax)
ans =  4

Note you can get both values using one logical index:

>> idx = u<umin | u>umax;
>> nnz(idx)
ans =  4
>> nnz(~idx)
ans =  6

[Rengin]

Thanks it is very practical!