[yt-dev] Field naming proposal

[Matthew Turk]

Hi Cameron,

On Tue, Dec 23, 2014 at 11:56 AM, Cameron Hummels <chummels at gmail.com>
wrote:

> Hi Nathan,
>
> Thanks for your hard work on this PR (along with Ben Thompson).  The
> naming convention that I suggested in the issue a few weeks back (
> https://bitbucket.org/yt_analysis/yt/issue/947/consistent-field-naming-for-spherical-and)
> and in the discussion on your PR also matches with past convention.  It is
> slightly different than what you propose, but seems (to me at least) to be
> more easy to read because the adjective comes before the noun (e.g.
> spherical position) instead of the reverse (e.g. position spherical).
>
>
I'm neutral to both of these, in that I am broadly neutral about the
increasingly nested set of modifiers.  If forced, I think I'd go with your
proposed convention.

What would be a lot nicer, in my opinion, would be if we had a way to do
this more generically.  Like,

with data_object.rotate( ... ):
    prof1d = create_profile(data_object, "particle_position_x",
"particle_mass")

and then just get rid of all the nested modified field names.  But I don't
really think this is feasible.

-Matt


> Where proposed naming convention #1 is:
>
> (field_type, "<particle?>_<position/velocity>_<coordinate_system>_<coordinate>")
> e.g. ('all', 'particle_position_spherical_phi')
>
> Proposed naming convention #2 is:
>
> (field_type, "<particle?>_<coordinate_system
> >_<position/velocity>_<coordinate>") e.g. ('all',
> 'particle_spherical_position_phi')
>
> Here are all of the relevant gas and particle fields each convention:
>
> *Cartesian* (convention #1 & #2 are the same)
>
> ('index', 'x')
> ('index', 'y')
> ('index', 'z')
> ('gas', 'velocity_x')
> ('gas', 'velocity_y')
> ('gas', 'velocity_z')
>
> ('all', 'particle_position_x')
> ('all', 'particle_position_y')
> ('all', 'particle_position_z')
> ('all', 'particle_velocity_x')
> ('all', 'particle_velocity_y')
> ('all', 'particle_velocity_z')
>
> Convention #1 & #2 differ for the fields of cartesian position relative to
> the 'center' and 'normal' field parameters for the origin and z-vector:
>
> #1 vs #2
> ('all', 'particle_position_relative_x')  vs. ('all',
> 'particle_relative_position_x')
> ('all', 'particle_position_relative_y')  vs. ('all',
> 'particle_relative_position_y')
> ('all', 'particle_position_relative_z')  vs. ('all',
> 'particle_relative_position_z')
> ('all', 'particle_velocity_relative_x')  vs. ('all',
> 'particle_velocity_position_x')
> ('all', 'particle_velocity_relative_y')  vs. ('all',
> 'particle_velocity_position_y')
> ('all', 'particle_velocity_relative_z')  vs. ('all',
> 'particle_velocity_position_z')
>
> *Spherical*:
> #1 vs #2
>
> ('index', 'spherical_phi')
> ('index', 'spherical_radius')
> ('index', 'spherical_theta')
> ('gas', 'velocity_spherical_phi') vs      ('gas', 'spherical_velocity_phi')
> ('gas', 'velocity_spherical_theta') vs   ('gas',
> 'spherical_velocity_theta')
> ('gas', 'velocity_spherical_radius') vs ('gas',
> 'spherical_velocity_radius')
>
> ('all', 'particle_position_spherical_phi') vs      ('all',
> 'particle_spherical_position_phi')
> ('all', 'particle_position_spherical_theta') vs   ('all',
> 'particle_spherical_position_theta')
> ('all', 'particle_position_spherical_radius') vs ('all',
> 'particle_spherical_position_radius')
> ('all', 'particle_velocity_spherical_phi') vs       ('all',
> 'particle_spherical_velocity_phi')
> ('all', 'particle_velocity_spherical_theta') vs    ('all',
> 'particle_spherical_velocity_theta')
> ('all', 'particle_velocity_spherical_radius') vs  ('all',
> 'particle_spherical_velocity_radius')
>
> *Cylindrical*:
> #1 vs #2
>
> ('index', 'cylindrical_phi')
> ('index', 'cylindrical_radius')
> ('index', 'cylindrical_theta')
> ('gas', 'velocity_cylindrical_phi') vs      ('gas',
> 'cylindrical_velocity_phi')
> ('gas', 'velocity_cylindrical_theta') vs   ('gas',
> 'cylindrical_velocity_theta')
> ('gas', 'velocity_cylindrical_radius') vs ('gas',
> 'cylindrical_velocity_radius')
>
> ('all', 'particle_position_cylindrical_phi') vs      ('all',
> 'particle_cylindrical_position_phi')
> ('all', 'particle_position_cylindrical_theta') vs   ('all',
> 'particle_cylindrical_position_theta')
> ('all', 'particle_position_cylindrical_radius') vs ('all',
> 'particle_cylindrical_position_radius')
> ('all', 'particle_velocity_cylindrical_phi') vs       ('all',
> 'particle_cylindrical_velocity_phi')
> ('all', 'particle_velocity_cylindrical_theta') vs    ('all',
> 'particle_cylindrical_velocity_theta')
> ('all', 'particle_velocity_cylindrical_radius') vs  ('all',
> 'particle_cylindrical_velocity_radius')
>
>
> So what does the community think would be the best system here?  #1 or
> #2?  Either way it goes, I think this is a big improvement over the
> previous naming convention that had general inconsistencies.
>
> Cameron
>
>
> On Tue, Dec 23, 2014 at 11:01 AM, Nathan Goldbaum <nathan12343 at gmail.com>
> wrote:
>
>> Hi all,
>>
>> I've just issued a pull request that bears some developer discussion.
>>
>> Right now yt is a bit of a wild west in terms of the field naming
>> convention for fields that reference a coordinate system.  See for example,
>> see issue 947:
>>
>>
>> https://bitbucket.org/yt_analysis/yt/issue/947/consistent-field-naming-for-spherical-and
>>
>> I'd like to propose a naming convention for fields that reference a
>> coordinate system.  Gas and particle fields should be of the form:
>>
>> (field_type, "<particle?>_<vector_field_name>_<coordinate>")
>>
>> while index fields for coordinates should be of the form:
>>
>> ("index", "<coordinate>")
>>
>> This fits within our existing field naming convention for cartesian
>> coordinates, e.g.:
>>
>> ("gas", "velocity_x")
>> (ptype, "particle_velocity_y")
>>
>> as well as our convention for index coordinate fields, e.g.:
>>
>> ("index", "x")
>> ("index", "spherical_theta")
>>
>> This means that index fields do not need to explicitly reference
>> themselves as positions.  So we *won't* have field names like:
>>
>> ("index", "position_x")
>>
>> I don't like the above construction because it's a bit redundant ("index"
>> implies that we are talking about a position or something similar).
>>
>> Some existing field names will need to be changed to fit this.  In
>> particular, some of the index fields will need to be renamed to be more
>> verbose ("index", "spherical_r") becomes ("index", "spherical_radius") and
>> (ptype, "particle_spherical_position_radius") becomes (ptype,
>> "particle_position_spherical_radius").
>>
>> Wherever an existing field name needs to change, I propose we mark the
>> existing field name for deprecation, stub it out, and make it an alias for
>> the field with the new field name.  In a future release, we can then remove
>> the deprecated fields.
>>
>> I've implemented this for the particle fields (for the most part) in PR
>> 1378:
>>
>> https://bitbucket.org/yt_analysis/yt/pull-request/1378
>>
>> I'm happy to update the field naming YTEP if this proposed field naming
>> scheme gets approval in this thread.
>>
>> What do you all think?  Question, concerns?
>>
>> -Nathan
>>
>>
>>
>> _______________________________________________
>> yt-dev mailing list
>> yt-dev at lists.spacepope.org
>> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
>>
>>
>
>
> --
> Cameron Hummels
> Postdoctoral Researcher
> Steward Observatory
> University of Arizona
> http://chummels.org
>
> _______________________________________________
> yt-dev mailing list
> yt-dev at lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.spacepope.org/pipermail/yt-dev-spacepope.org/attachments/20141223/d0092243/attachment.html>
-------------- next part --------------
_______________________________________________
yt-dev mailing list
yt-dev at lists.spacepope.org
http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org