Culling or Selecting Points within a parameter whilst keeping original number of points

Hey,

Apologies if this is a very simple definition but I am new to grasshopper and am struggling to work around my problem. I am analyzing site temperature and would like to display the average daily temperature within a circle (each point being a individual day). I have extracted the data from ladybug, and have plotted the points within a circle. My question is how to select, or cull the irrelevant points in my project (any value not between 21 and 30) without losing the 365 points of the circle. At the moment I can only cull the pattern which would result in the original average temperatures not relating to the day. Please find attached my script and visual to help explain. The two circles are placed for reference to show the parameters of the points that I would like to remove from the definition.

Thanks in Advance,

J