Matt Knox (el 2007-05-03 a les 19:26:58 +0000) va dir::

> One slight problem with this approach is that columns can't be dynamically
> added/removed from tables (as far as I know), so that boolean column would
> always need to be there even if the MaskedArray had no masked values to 
> account
> for the possibility of masked values being appended to it in the future. This
> wouldn't impact functionality, but would impact performance a bit.

Well, I guess that compression (even at a low ratio) would alleviate the
I/O burden of storing the mask side to side with data, specially if most
elements in the mask have the same values (e.g. when nearly all data
points have known values).

::

        Ivan Vilata i Balaguer   >qo<   http://www.carabos.com/
               Cárabos Coop. V.  V  V   Enjoy Data
                                  ""

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