To compare two floating point values with a given precision, just use the SameValue()
function from Math unit or its sibbling CompareValue().
if SameValue(456.9067896, 456.90679, 1E-5) then ...
You can specify the precision on which the comparision will take place.
Or you can use a currency
value, which has fixed arithmetic precision of 4 digits. So, it won't have rounding issue any more. But you can not do all mathematic computation with it (huge or tiny numbers are not handled properly): its main use is for accounting computations.
You should better never use string
representations to compare floats, since it may be very confusing, and do not have good rounding abilities.