CentralAlignment¶
- class halotools.empirical_models.CentralAlignment(central_alignment_strength=1.0, prim_gal_axis='major', **kwargs)[source]¶
Bases:
object
alignment model for central galaxies in host-halos
- Parameters:
- central_alignment_strengthfloat
[-1,1] bounded number indicating alignment strength
- prim_gal_axisstring, optional
string indicating which galaxy principle axis is correlated with the halo alignment axis. The options are:
major
,intermediate
, andminor
.- alignment_keyslist
A list of strings indicating the keywords for the x,y- and z components of the halo alignment vector. Deafult is [‘halo_axisA_x’, ‘halo_axisA_y’, ‘halo_axisA_z’].
Notes
If the kwargs or table contains a key “alignment_strength”, when populating a mock, this will be used instead of the
central_alignment_stregth
parameter passed during intialization. This is how varying the alignment strength as a function of galaxy/halo properties is handeled.Methods Summary
assign_central_orientation
(**kwargs)Assign a set of three orthoganl unit vectors indicating the orientation of the galaxies' major, intermediate, and minor axis
Methods Documentation
- assign_central_orientation(**kwargs)[source]¶
Assign a set of three orthoganl unit vectors indicating the orientation of the galaxies’ major, intermediate, and minor axis
- Parameters:
- halo_axisA_x, halo_axisA_y, halo_axisA_zarray_like
x,y,z components of halo alignment axis
- Returns:
- major_aixs, intermediate_axis, minor_axisnumpy nd.arrays
arrays of galaxies’ axes