[yt-users] yt for RAMSES

[Nicolas Gillet]

Hello,

I am Nicolas, I am a new YT user. I am working on RAMSES simulations.

- First I have noted a "bug" (or misunderstand) in the yt.load of RAMSES 
data.
It takes all the times of the output as 'code_units' times, which is not 
the case.
The output times are negative and I think it needs a FLRW integration to 
be converted in conventional time.
Using directly the 'code_units_time' to convert in cgs time is wrong.
So all the times are false in the loaded yt data, simulation time, 
particles ages ....

- My second question is link to the first point. With ramses there is a 
tool (getstarlist.f90) that extract only the stars in a .txt file, with 
the ages in Myr with the proper conversion.
My idea is to load those new data in yt, and creat a new field for 
particles, with this correct ages.
With the example I creat a filter to isolate the stars from 'all' 
particles, and it apear in the derived_field_list.
But I do not find a way to creat a new field for this filtered particles 
and even for the 'all' particles.

I would like to have the possibility to have a field ad['star', 
'my_own_ages'] or ad['all', 'my_own_ages'].

What I have done:

### isolate star particles
def _star(pfilter, data):
     filter = data['all', 'particle_age'] < 0
     return filter

add_particle_filter('star', function=_star, filtered_type='all', 
requires=['particle_age','particle_identifier'])
ds.add_particle_filter('star')

### stars are correctly created ok

### create a global star_age field, not linked to 'all' or 'star'
def _star_age(field, data):
     T = data['particle_age'].in_units('Myr') * 0.
     selec_stars = np.where(data['particle_age'] < 0)[0]
     T[selec_stars] = Stars[5,:] * yt.units.Myr
     return T

ds.add_field('star_age', function=_star_age, units='Myr')



What I try:

def _star_age2(field, data):
     T = data['all','particle_age'].in_units('Myr') * 0.
     selec_stars = np.where(data['all','particle_age'] < 0) [0]
     T[selec_stars] = Stars[5,:] * yt.units.Myr
     return T

ds.add_field(('all','star_age2'), function=_star_age2, units='Myr')

### ('all','star_age2') appear in the derived_field_list but

ad['all','star_age2'] => YTFieldTypeNotFound: Could not find field 'all'


Thank you for your help,
Nicolas



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.spacepope.org/pipermail/yt-users-spacepope.org/attachments/20160114/2fbc2b3c/attachment.htm>
-------------- next part --------------
_______________________________________________
yt-users mailing list
yt-users at lists.spacepope.org
http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org