[Numpy-discussion] Adding .abs() method to the array object

[josef.pktd at gmail.com]

On Sat, Feb 23, 2013 at 3:33 PM, Robert Kern <robert.kern at gmail.com> wrote:
> On Sat, Feb 23, 2013 at 7:25 PM, Nathaniel Smith <njs at pobox.com> wrote:
>> On Sat, Feb 23, 2013 at 3:38 PM, Till Stensitzki <mail.till at gmx.de> wrote:
>>> Hello,
>>> i know that the array object is already crowded, but i would like
>>> to see the abs method added, especially doing work on the console.
>>> Considering that many much less used functions are also implemented
>>> as a method, i don't think adding one more would be problematic.
>>
>> My gut feeling is that we have too many methods on ndarray, not too
>> few, but in any case, can you elaborate? What's the rationale for why
>> np.abs(a) is so much harder than a.abs(), and why this function and
>> not other unary functions?
>
> Or even abs(a).


my reason is that I often use

arr.max()
but then decide I want to us abs and need
np.max(np.abs(arr))
instead of arr.abs().max() (and often I write that first to see the
error message)

I don't like
np.abs(arr).max()
because I have to concentrate to much on the braces, especially if arr
is a calculation

I wrote several times
def maxabs(arr):
    return np.max(np.abs(arr))

silly, but I use it often and np.is_close is not useful (doesn't show how close)

Just a small annoyance, but I think it's the method that I miss most often.

Josef


>
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> Robert Kern
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