MATLAB: Find values outside of a range when calculating residuals.

Question

Hi, I'm trying to find all my residuals above 3 and below minus 3 and extract the corresponding records to an excel sheet. I know there are 447 values which are outside of the range out of the total 14792.

My approach has been to use the find function to find all records within the range and then somehow make it so matlab returns all records outside this range, but I'm not familiar with how to do this and so was hoping for some help here.

The code I have so far is simply:

W=find(res>=-3 & res<3)

>> length(W)

ans =

       14345

Where length(W) is the number of records within the range 3 to -3, whereas I need the other 447 values outside of this range.

The variable res is a 14972 x 1 double

Thanks for any help.

Answer 1

I would use ‘logical indexing’ here:

L = (res>=-3) & (res<3);                % Logical Index Of ‘res’ Values Within Limits
In = W(L);
Out = W(~L);

If you need the indices, use find:

InIdx = find(L);
OutIdx = find(~L);