[Numpy-discussion] New numpy functions: filled, filled_like

[Matthew Brett]

Hi,

On Sun, Jan 13, 2013 at 5:27 PM, Nathaniel Smith <njs at pobox.com> wrote:
> Hi all,
>
> PR 2875 adds two new functions, that generalize zeros(), ones(),
> zeros_like(), ones_like(), by simply taking an arbitrary fill value:
>   https://github.com/numpy/numpy/pull/2875
> So
>   np.ones((10, 10))
> is the same as
>   np.filled((10, 10), 1)
>
> The implementations are trivial, but the API seems useful because it
> provides an idiomatic way of efficiently creating an array full of
> inf, or nan, or None, whatever funny value you need. All the
> alternatives are either inefficient (np.ones(...) * np.inf) or
> cumbersome (a = np.empty(...); a.fill(...)). Or so it seems to me. But
> there's a question of taste here; one could argue instead that these
> just add more clutter to the numpy namespace. So, before we merge,
> anyone want to chime in?
>
> (Bonus, extra bike-sheddy survey: do people prefer
>   np.filled((10, 10), np.nan)
>   np.filled_like(my_arr, np.nan)
> or
>   np.filled(np.nan, (10, 10))
>   np.filled_like(np.nan, my_arr)
> ?)

I remember there has been a reluctance in the past to add functions
that were two-liners.  I guess the problem might be that the namespace
fills up with many similar things.  Is this a worry?

Best,

Matthew