[Russell Warren, playing w/ time.clock() on Windows] > ... > Based on this code and some quick math it confirms that not only will > the rollover be a looong way out, but that there will not be any loss > in precision until ~ 30 years down the road. Checking my math: > > (float(10**16 + 1) - float(10**16)) == 0 > (float(10**15 + 1) - float(10**15)) == 1 > ie: our double precision float can resolve unity differences out to > at least 10**15 > Assuming 1 us/count we have 10**15 us / (3.15E13 us/year) = 31.7 yrs
It's about 9x larger than that (given your assumptions). A double has exactly 53 significand bits on almost all boxes now: >>> 2.**53+1 - 2.**53 0.0 >>> 2.**53 - (2.**53-1) 1.0 That is, all integers with absolute value <= 2**53 are exactly representable as doubles. -- http://mail.python.org/mailman/listinfo/python-list
