On Apr 11, 6:14 pm, bdsatish <[EMAIL PROTECTED]> 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
If you care about such details, you may be better off using decimals
instead of floats.
> 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 ?
import decimal
decimal.Decimal("1.5").to_integral(
rounding=decimal.ROUND_HALF_EVEN)
decimal.Decimal("2.5").to_integral(
rounding=decimal.ROUND_HALF_EVEN)
ROUND_HALF_EVEN is the default, but maybe that can be changed, so
explicit is safest.
If you really insist,
import decimal
def my_round(f):
d = decimal.Decimal(str(f))
rounded = d.to_integral(rounding=decimal.ROUND_HALF_EVEN)
return int(rounded)
Graham
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