Hi pytable users,

Perhaps everyone is on vacation or my questions are too stupid...??
Anyway here comes another question from a PyTables newbie

I have recently realized that numpy.memmap recarray does not give me
large enough files on my Win32 OS for me to handle my several GB data
files, so I have turned to PyTables.

So one of the tasks I am facing is getting Descriptor classes (or
equivalent dictionaries) to use for table.createTable.

What I have is a bunch of loong numpy.dtype declarations defining the
numpy recarrays I am using. (They are not nested, they just have many
fields)

One path is to implement a series of IsDescription classes as
equivalents of the dtypes I've defined. That is a very boring and
seems redundant. It is also bad for maintenance as when I adjust or
add new recarray dtypes i have to remember to also update the
Description classes. I was therefore hoping that there was either a
constructor or a factory method available for Description, such that
you could get an equivalent Description class from, e.g.,
Description.from_dtype(), just as there is for Atom:
Atom.from_dtype().

However, that does not seem to be the case?

I've noted I can do the reverse from a table instance:
table.description._v_dtype

Am I overlooking something?

If not I will get on with implementing it myself (it would be fun
actually, much funnier than manually defining all them classesI just
don't want to redo it, if it has already been done).

Cheers,
Kim

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