Rounding a number to nearest even

[bdsatish]

On Apr 11, 4:24 pm, cokofree... at gmail.com wrote:
> On Apr 11, 1:19 pm, cokofree... at gmail.com wrote:
>
> > couldn't you just do.
>
> > #untested
> > new_round(n):
> >   answer = round(n)
> >   # is answer now odd
> >   if answer % 2:
> >     return answer - 1
> >   else:
> >     return answer
>
> Whoops, this also affects odd numbers...
>
> Will try and find a GOOD solution later...
>
> Strange request though, why do you need it that way, because 2.5 is
> CLOSER to 3 than to 2...

It also fails for negative numbers. For -2.5 as input, I get -4.0
whereas I expect -2.0

This is a lengthy solution I came-up with:

def round_even(x):
    temp = round(abs(x))
    if (abs(x) - 0.5)%2.0 == 0.0:  temp=temp-1
    return signum(x)*temp

def signum(x):
    if x>0:     return 1
    if x<0:     return -1
    return 0

But i guess there are better ways. I need it 'cos I'm translating some
code from Mathematica to Python. And Math..ica's Round[ ] behaves this
way (as I requested)