[Numpy-discussion] round() and abs() Ufuncs???

[Chris Barker]

Hi all,

I was recently surprised to find that there are no round(0 or abs()
Ufuncs with Numeric. I'm imagining that they might exist under other
names, but if not, I submit my versions for critique (lightly tested)

-Chris

from Numeric import *

def Uabs(a):
    """

    A Ufunc version of the Python abs() function

    """
    a = asarray(a)
    if a.typecode() == 'D' or a.typecode() == 'F':# for complex numbers
        return sqrt(a.imag**2 + a.real**2)
    else:
        return where(a < 0, -a, a)

def Uround(a,n=0):
    """

    A Ufunc version of the Python round() function. It should behave in
the same way

    Note: I think this is the right thing to do for negative numbers,
    but not totally sure. (Uround(-0.5) = 0, but Uround(-0.5000001) =
-1)

    It won't work for complex numbers

    """

    a = asarray(a)
    n = asarray(n)
    return floor((a * 10.**n) + 0.5) / 10.**n
    



-- 
Christopher Barker,
Ph.D.                                                           
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