Question

I want to round according to arbitrary divisions, e.g. I get a number from 0 to 1 and I want to round it according to divisions into 48ths, e.g. if I get something like 5/96, i want either 2/48 or 3/48. What’s a good formula to do that?

Answer 1

The same as with rounding to decimal signs. If you have n ‘divisions’ and number x, do round(x*n)/n.
In your example, it’ll be round((5/96)*48)/48 = round(2.5)/48 = 2/48

round can be replaced with floor or ceil, depending on the direction you want.