"Is it also need to use round function to verify that my var has no decimal point?"
No need.
Firstly, You need make sure the variable is a RATIO by your eyeball.
Here I multiply 100 is for taking account of two of decimal point.
E.X.
0.3456 --> 34.56
because my cutpoint is integer value, multiply 100 is to take care of .34 .
.0056 is not what I care about, therefore it does not matter if using ROUNG(x,0.01) or not.
"Is the action of multiply by 100 will remove the decimals ??? or need also use round???"
No. not remove decimal point. No need to use ROUND() as I said above. My GA code would not take into account of it.
"as I see need also use round function."
You could use ROUND(). but My code would not take care of it. So using ROUND() does not meaning anything.
BTW, After you get cutoff value ,you need to transform it back into original value by multiply 0.01 .