Hi,

Following the commit (https://github.com/yt-project/yt/pull/2259), I am unable to access the field 'particle_age' which I was able to do before. The list of fields I currently have for my RAMSES data is:

('all', 'mesh_id')

('all', 'particle_angular_momentum')

('all', 'particle_angular_momentum_magnitude')

('all', 'particle_angular_momentum_x')

('all', 'particle_angular_momentum_y')

('all', 'particle_angular_momentum_z')

('all', 'particle_cylindrical_velocity_theta')

('all', 'particle_cylindrical_velocity_z')

('all', 'particle_extra_field_1')

('all', 'particle_extra_field_2')

('all', 'particle_extra_field_3')

('all', 'particle_extra_field_4')

('all', 'particle_extra_field_5')

('all', 'particle_identity')

('all', 'particle_index')

('all', 'particle_mass')

('all', 'particle_ones')

('all', 'particle_position')

('all', 'particle_position_cylindrical_radius')

('all', 'particle_position_cylindrical_theta')

('all', 'particle_position_cylindrical_z')

('all', 'particle_position_relative')

('all', 'particle_position_relative_x')

('all', 'particle_position_relative_y')

('all', 'particle_position_relative_z')

('all', 'particle_position_spherical_phi')

('all', 'particle_position_spherical_radius')

('all', 'particle_position_spherical_theta')

('all', 'particle_position_x')

('all', 'particle_position_y')

('all', 'particle_position_z')

('all', 'particle_radial_velocity')

('all', 'particle_radius')

('all', 'particle_refinement_level')

('all', 'particle_specific_angular_momentum')

('all', 'particle_specific_angular_momentum_x')

('all', 'particle_specific_angular_momentum_y')

('all', 'particle_specific_angular_momentum_z')

('all', 'particle_spherical_position_phi')

('all', 'particle_spherical_position_radius')

('all', 'particle_spherical_position_theta')

('all', 'particle_spherical_velocity_phi')

('all', 'particle_spherical_velocity_radius')

('all', 'particle_spherical_velocity_theta')

('all', 'particle_velocity')

('all', 'particle_velocity_cylindrical_radius')

('all', 'particle_velocity_cylindrical_theta')

('all', 'particle_velocity_cylindrical_z')

('all', 'particle_velocity_magnitude')

('all', 'particle_velocity_relative')

('all', 'particle_velocity_relative_x')

('all', 'particle_velocity_relative_y')

('all', 'particle_velocity_relative_z')

('all', 'particle_velocity_spherical_phi')

('all', 'particle_velocity_spherical_radius')

('all', 'particle_velocity_spherical_theta')

('all', 'particle_velocity_x')

('all', 'particle_velocity_y')

('all', 'particle_velocity_z')

('all', 'relative_particle_position')

('all', 'relative_particle_position_x')

('all', 'relative_particle_position_y')

('all', 'relative_particle_position_z')

('all', 'relative_particle_velocity')

('all', 'relative_particle_velocity_x')

('all', 'relative_particle_velocity_y')

('all', 'relative_particle_velocity_z')


I tried the 'extra_fields_x' but none of them match with the dimensions of time. Any help is appreciated and thanks.