Basic Usage: kdGroupFinder inputfile zmin zmax frac_area [fluxlim] [color] [wcenvalues 1-6] [Bsat_values 1-4] [wchi_values 1-4]> out

• inputfile: the galaxy file in which to find the groups (format described below)
• zmin: minimum redshift. Mainly for volume-limited samples. For flux-limited, use value below all galaxies in file.
• zmax: maximum redshift. Mainly for volume-limited samples. For flux-limited, use value above all galaxies in file.
• fracarea: the fraction of the sky covered by the galaxy sample. (Used to calculate volumes).
• fluxlim - 1/0 to delineate if the input file is flux-limted or volume-limited.
• color - 1/0 will the input file have color information (for each galaxy, 1=quiescent, 0=star-forming).
• wcenvalues - these are the 6 free parameters that govern the weights on the total group luminosity. These are taken from Equation (4) in the SDSS Application paper (Tinker 2020).
  • wcen[1] - omega_L,sf
  • wcen[2] - sigma_sf
  • wcen[3] - omega_L,q
  • wcen[4] - sigma_q
  • wcen[5] - omega_0,sf
  • wcen[6] - omega_0,q
• Bsat_values - these are the 4 free parameters that set the satellite probability threshold. Taken from Equation (3).
  • Bsat[1] - beta_0,q
  • Bsat[2] - beta_L,q
  • Bsat[3] - beta_0,sf
  • Bsat[4] - beta_L,sf
• wchi values - these are the 4 free parameters that set the weights by normalized galaxy property chi. Taken from Equation (5).
  • wchi[1] - omega_chi,0,sf
  • wchi[2] - omega_chi,0,q
  • wchi[3] - omega_chi,L,sf
  • wchi[4] - omega_chi,L,q

Example Usage, taken randomly from the posterior distribution of parameters in the MCMC anlaysis in the paper.

• kdGroupFinder_omp sdss_fluxlim_v1.0.dat 0 1 0.179 1 1 13.1 2.42 12.9 4.84 17.4 2.67 -0.92 10.25 12.993 -8.04 2.68 1.10 2.23 0.48 >outxx

For formats of the input and outout files, see the file descriptions at the project's web page. Note that the actual input file for the catalog is provided.

NB: The code expects a tabulated halo mass function is in the run directory, in a file called "halo_mass_function.dat." I have supplied one in the repo for the Bolshoi Planck cosmology using the Tinker et al (2008) halo mass function.

NB: The code will run for 5 iterations and then output the current state of the group catalog. Five is usually a reasonable number for convergence of the satellite fraction to a couple of percent. This can be modified inside the code. There are several features currentl "turned off," which involve populating the halos of a simulation with HODs, and tabulating the L_sat values. These can be turned on with little effort in the main() function, but user-defined input is required to make them actually run, by supplying the necessary files.