Discarding values higher than ranges

Hi everyone! 

                       I need some help. What I am trying to do is to take an array of 51 elements and plotting its PSD and applying statistics further.

But before that I want to scan that either the array elements are within my define ranges. So, if the amplitudes of these all 51 values are less than 8 and greater than -8 then pass it to power spectrum. But if this is not the case then go back and take new 51 elements array. 

Now question is how to discard this array (which elements are not in range) and replace it with new one (coming from stimulate signal). Because I don't want to see NaN in ArrayM but values continously coming within my defined ranges.

I hope that I delivered my point clearly. 

Here's my messy code sorry for that. :smileyhappy:

Thank You

Regards 

AG