This is a general description file for HOD_MN.

How to run with various options:

===Galaxy Number Density===

To run with galaxy number density free to move, set M_min>0 and free[0] to 1.  Fits 
will then assume that the error on the number density is 10% of the number density.
  Otherwise, set GALDENS_ERR to the error on the number density.  Typical values 
are around 1% or so for 3e-4 (Mpc/h)^-3 in a (640 Mpc/h)^3 box.

To run with galaxy number fixed, set free[0]=0, free[1]=0 and M_min=0.  M_min will 
be adjusted given the other parameters to maintain a fixed number density.  
WARNING:  This occasionally leads to bad behavior, when, e.g., M_min has limited 
effect on the HOD, or when an odd number density/HOD combination requires a very 
high or very low M_min.