Re: [Pytables-users] Clear chunks from CArray

[Anthony S. <sc...@gm...>]

On Mon, Aug 5, 2013 at 3:14 PM, Giovanni Luca Ciampaglia <
glc...@gm...> wrote:

> Hi Anthony,
>
> what do you mean precisely? I tried
>
> del ca[:,:]
>
> but CArray does not support __delitem__. Looking in the documentation I
> could
> only find a method called remove_rows, but it's in Table, not CArray.
> Maybe I am
> missing something?
>

Huh, it should...  This is definitely an oversight on our part.  If you
could please open an issue for this -- or better yet -- write a pull
request that implements delitem, that'd be great!

So I think you are right that there is no current way to delete rows from a
CArray.  Oops!  (Of course, I may still be missing something as well).

It looks like EArray also has this problem too, otherwise I would just tell
you to use that.

Be Well
Anthony


>
> Thank,
>
> Giovanni
>
> On Mon 05 Aug 2013 03:43:42 PM EDT,
> pyt...@li...
> wrote:
> >
> >> Hello Giovanni, I think you may need to del that slice and then possibly
> >> repack. Hope this helps. Be Well Anthony On Mon, Aug 5, 2013 at 2:09 PM,
> >> Giovanni Luca Ciampaglia < glc...@gm...> wrote:
> >>> Hello all,
> >>>
> >>> is there a way to clear out a chunk from a CArray? I noticed that
> setting
> >>> the
> >>> data to zero actually takes disk space, i.e.
> >>>
> >>> ***
> >>> from tables import open_file, BoolAtom
> >>>
> >>> h5f = open_file('test.h5', 'w')
> >>> ca = h5f.create_carray(h5f.root, 'carray', BoolAtom(),
> shape=(1000,1000),
> >>> chunkshape=(1,1000))
> >>> ca[:,:] = False
> >>> h5f.close()
> >>> ***
> >>>
> >>> The resulting file takes 249K ...
> >>>
> >>> Best,
> >>>
> >>> --
> >>> Giovanni Luca Ciampaglia
> >>>
> >>> Postdoctoral fellow
> >>> Center for Complex Networks and Systems Research
> >>> Indiana University
> >>>
> >>> ? 910 E 10th St ? Bloomington ? IN 47408
> >>> ?http://cnets.indiana.edu/
> >>> ?gci...@in...
> >>>
> >
>
>
>
> --
> Giovanni Luca Ciampaglia
>
> Postdoctoral fellow
> Center for Complex Networks and Systems Research
> Indiana University
>
> ✎ 910 E 10th St ∙ Bloomington ∙ IN 47408
> ☞ http://cnets.indiana.edu/
> ✉ gci...@in...
>
>
>
> ------------------------------------------------------------------------------
> Get your SQL database under version control now!
> Version control is standard for application code, but databases havent
> caught up. So what steps can you take to put your SQL databases under
> version control? Why should you start doing it? Read more to find out.
> http://pubads.g.doubleclick.net/gampad/clk?id=49501711&iu=/4140/ostg.clktrk
> _______________________________________________
> Pytables-users mailing list
> Pyt...@li...
> https://lists.sourceforge.net/lists/listinfo/pytables-users
>