when float number is above 0.5 and when is below 0.5?

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Dear Collegues,

i have read a lot of papers and nowhere I can find any solution or solutions to verified when float number is above 0.5 and when below 0.5

example:

number 0.2 -> below 0.5
number 0.55 -> above 0.5

what I have : to verified in algorithm : number 1.345 , and I;d like to know how to check that is more than 1.5 or les than 1.5? I cant check by if 1.345 > 1.5 then print("above") :)

it is any solution algoritms how compute calculate it?

Now i will describe the problem: I have a number which I divide by 2: for example

number =  1699
1 849.5
2 424.75
3 212.375
4 106.1875
5 53.09375
6 26.546875
7 13.2734375
8 6.63671875
9 3.318359375
10 1.6591796875

the last line - "10" there is 1.6591796875 -> it tranlated -> 1 * 2^10 + 2^10 * 0.6591796875 = 1699

and know -> I only know that there is value x which is 1.6591796875 , but I don't know this exactly number , but only know there is 1 plus rest. so I can substract from 1.6591796875 - 1 = to get rest : 0.6591796875 -> and here how to check it is more than 0.5 or less than 0.5?