Is switch accept 2 nd family that means real?

Question

switch accept only 1 and 3 family

Answer 1

I don't understand your question. Could you post an example code that shows what you want to do?

Answer 2

Seems new concept. .please teach me

Answer 3

Floats are not precise enough anyway. If you do a few calculations where you know the result might be 0, then in some cases you end up with a value VERY close to 0 but not 0.
You can only use integral types, meaning int, char....