How to get excel to flash fill by learning changes to formula

Here is my formula for the first 3 study's:


=SUMIF(Study_ID,LEFT(1,1),F:F)
=SUMIF(Study_ID,LEFT(2,1),F:F)
=SUMIF(Study_ID,LEFT(3,1),F:F)

I need to add the values in column F for each study and not for each subset. Each study is represented by the numbers before the period (eg study id 13.3 is study 13), that is why I have the left function. If there is a value of 1 in column F for study ID's 1.1 and 1.3 but not 1.2, I need excel to give me the sum of 2. I need this done for all studies and not each study ID. There are over 300 studies and over 700 study ID's so it would be very painful to do manually. Can I do this using the flash fill function in excel 2013? Thank you very much for your help.