Re: [Gretl-users] error with null list
Riccardo (Jack) Lucchetti schrieb:
Ok, I see what you mean now. If I'm not mistaken, your idea is to use the
include statement to bring back into gretl some objects (presumably matrices),
previously generated outside by a python script.
exactly
Allin and I had started thinking about a similar mechanism some months ago:
the only difference was that I had thought of using Ox instead of python. I
even managed to write a working prototype of an exchange mechanism that worked
as follows.
Indeed sounds very similar. Of course python/numpy is truly free, unlike
ox. (BTW, check out www.scipy.org) OTOH I would also be interested in
making a gretl frontend to Ox's Ssfpack (Kalman filter) this way. Or do
you know a truly free package comparable to Ssfpack? (But this is
getting OT...)
First, let's define the concept of a "binary bundle". A binary bundle is a
binary file which contains one or more objects. An object can be
1) a scalar
2) a matrix
3) a dataset
4) a model
I would also add: 5) some text, comment, etc.
Why does it have to be binary? Human-readable is an advantag IMO. Unless
you have tons of data, but I doubt you would be using gretl then (no
offense...).
Now, everything that's needed to shuffle stuff to/from gretl is
the ability,
by gretl and the helper application (Ox, python, R, scilab, whatever) to read
and write bundles. I had come to the point of writing an Ox class for this,
and the corresponding C functions, which we never merged into gretl. But if
you think that you can write a corresponding set of functions in python, then
we wouldn't need to mess with run/include.
If I understand you correctly, then yes I can do the helper app side and
bundle reading/writing in python. So if a 'bundle_read' facility is much
more simpler than enabling 'include/run' in gretl functions, fine with me.
I think this would provide a very neat way to do what I assume you need.
However, the coding effort is definitely not trivial. Could we schedule this
for 1.7.0?
What if you start out just with the ability to read in "bundles" with
genr/matrix/print commands (for scalars/matrices/text). Essentially just
opening the file and executing the literal contents as if the user typed
them in directly. like a limited version of 'run'. That wouldn't be so
difficult, would it?
(Should we take this off the user list? but keep me cc-ed please, or
maybe I should subscribe to gretl-devel...)
-sven