[yt-dev] Issue #1163: particle angular momentum profile error (yt_analysis/yt)

[Anonymous]

New issue 1163: particle angular momentum profile error
https://bitbucket.org/yt_analysis/yt/issues/1163/particle-angular-momentum-profile-error

Anonymous:

Hi yt developer

I wrote the following script to compute the particle angular momentum
===============================
import matplotlib as matplotlib
matplotlib.use('Agg')
import yt
import yt.units as units
import numpy as np
import matplotlib.pyplot as plt

def _partradiuspc(field, data):
    return data[('all','particle_radius')].in_units('pc')
yt.add_field('partradiuspc', function=_partradiuspc,
particle_type=True, units="pc")

index = 45
Nbin= 100
rmax = 3000
ds = yt.load("../DD%04d/DD%04d" % (index,index))
ds.index
ad= ds.all_data()

center = ds.find_max(("gas", "density"))[1]
rmin = max([1.0e-3,2.0*ds.index.get_smallest_dx().in_units('pc')])

sphere = ds.sphere(center, rmax*units.pc)
bulk_velocity = sphere.quantities['BulkVelocity']()
sphere.set_field_parameter('bulk_velocity', bulk_velocity)

profile = yt.Profile1D(sphere, 'partradiuspc', Nbin, x_min=rmin,
x_max=rmax, x_log=True, weight_field=None)
profile.add_fields(('all', 'particle_angular_momentum_x'))
profile.add_fields(('all', 'particle_angular_momentum_y'))
profile.add_fields(('all', 'particle_angular_momentum_z'))

PartAngularMomentum = np.sqrt(profile[('all', 'particle_angular_momentum_x')]**2
                              + profile[('all',
'particle_angular_momentum_y')]**2
                              + profile[('all',
'particle_angular_momentum_z')]**2)

plt.plot(profile.x, PartAngularMomentum, label='Total',linestyle="-",color='r')

plt.xlabel('r [pc]')
plt.ylabel('pang')
===================================
And, I got the following error message
………………
Traceback (most recent call last):
  File "pang.py", line 26, in <module>
    profile = yt.Profile1D(sphere, 'partradiuspc', Nbin, x_min=rmin,
x_max=rmax, x_log=True, weight_field=None)
  File "/home/jhchoi/common/src/yt/yt/data_objects/profiles.py", line
411, in __init__
    self.x_field = data_source._determine_fields(x_field)[0]
  File "/home/jhchoi/common/src/yt/yt/data_objects/data_containers.py",
line 1001, in _determine_fields
    raise YTFieldNotFound((ftype,fname),self.ds)
yt.utilities.exceptions.YTFieldNotFound: Could not find field '('all',
'partradiuspc')' in DD0045.

If I remove "particle_type=True" in add_field, it works.
However, I am not sure that removing "particle_type=True" return correct output.

Thank you,
Junhwan