How to get a fraction from a float number?

While this is not what most people will want, but TS asked for fract as integer, here it is:

function fract(n){ return Number(String(n).split('.')[1] || 0); }
fract(1.23) // = 23
fract(123) // = 0
fract(0.0008) // = 8

function frac(f) {
    return f % 1;
}

hope that helps ;-)