On Apr 15, 11:22 am, Sjoerd Mullender <[EMAIL PROTECTED]> wrote: > Thomas Dybdahl Ahle wrote: > > On Fri, 2008-04-11 at 03:14 -0700, bdsatish wrote: > >> The built-in function round( ) will always "round up", that is 1.5 is > >> rounded to 2.0 and 2.5 is rounded to 3.0. > > >> If I want to round to the nearest even, that is > > >> my_round(1.5) = 2 # As expected > >> my_round(2.5) = 2 # Not 3, which is an odd num > > >> I'm interested in rounding numbers of the form "x.5" depending upon > >> whether x is odd or even. Any idea about how to implement it ? > > > This seams to work fine: > > evenRound = lambda f: round(f/2.)*2 > > >>>> [(f*.5, evenRound(f*.5)) for f in xrange(0,20)] > > [(0.0, 0.0),(0.5, 0.0), > > (1.0, 2.0), (1.5, 2.0), (2.0, 2.0), (2.5, 2.0), > > (3.0, 4.0), (3.5, 4.0), (4.0, 4.0), (4.5, 4.0), > > (5.0, 6.0), (5.5, 6.0), (6.0, 6.0), (6.5, 6.0), > > (7.0, 8.0), (7.5, 8.0), (8.0, 8.0), (8.5, 8.0), > > (9.0, 10.0), (9.5, 10.0)] > > No, this does not work:>>> [(f*.25, evenRound(f*.25)) for f in xrange(0,20)] > > [(0.0, 0.0), (0.25, 0.0), (0.5, 0.0), (0.75, 0.0), (1.0, 2.0), (1.25, > 2.0), (1.5, 2.0), (1.75, 2.0), (2.0, 2.0), (2.25, 2.0), (2.5, 2.0), > (2.75, 2.0), (3.0, 4.0), (3.25, 4.0), (3.5, 4.0), (3.75, 4.0), (4.0, > 4.0), (4.25, 4.0), (4.5, 4.0), (4.75, 4.0)] > > x.75 should be rounded up. > > -- > Sjoerd Mullender > > signature.asc > 1KDownload
even is closer to even.75 than even+1.25. Why should it be rounded up ? -- http://mail.python.org/mailman/listinfo/python-list
