Rounding to nearest int with numpy.rint() not consistent for .5

Question

numpy\'s round int doesn\'t seem to be consistent with how it deals with xxx.5

In [2]: np.rint(1.5)
Out[2]: 2.0

In [3]: np.rint(10.5)
Out[3]: 10.0
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Answer 1

The built-in round function seems to do what you want, although it only works on scalars:

def correct_round(x):
    try:
        y = [ round(z) for z in x ]
    except:
        y = round(x)    
    return y

and then to verify:

print correct_round([-2.5,-1.5,-0.5,0.5,1.5,2.5])
> [-3.0, -2.0, -1.0, 1.0, 2.0, 3.0]