README

#############################################################
Population dynamics code for pulsating active matter
#############################################################

The following is a complete, functioning population dynamics/cloning code exploring the biased ensembles of pulsating active matter.
Cloning component adapted from https://github.com/yketa/active_work.
It consists of a c++ program and some interface scripts written in bash. All files required to execute, run and calculate are included.

#############################################################
I. Compiling 
#############################################################

The c++ code can be easily compiled using (using GNU compilers):
	make -f make_clone
and will generate the executable 'cloning_def.exe'

#############################################################
II. Running the code
#############################################################

The code may then be ran using the script file `parallel_bias_runs.sh' and 'run_setup.slurm'. The first defines the range of bias to be 
considered (submitted as independent runs), while the latter specificies pulsating particle dynamic and cloning settings.
  
The output will consist of 'log_*.txt', 'cloning_*.dat' and 'g_log_*' files. The first are the result of the cloning simulation; 
the second is a saved output of the last timestep of the code which may be used to later re-start the simulation (if desired); 
and the third is the log of the self-adjusting control parameter. Note this latter will be empty if not using controlled simulations.

In addition, all controlled simulations require a calibration curve file as input. This will allow the algorithm to automatically adjust the control
parameter 'g' for a computed averaged value of the observable <O(s)>_bias given some value of bias, s, such that <O(g)>=<O(s)>_bias, where <.>_bias
indicates the results from cloning and <.> an unbiased average for a given value of 'g'. 
Calibration files may be generated with the same code using s=0 and different values of 'g'.

As an example, these output files are included in the folder for a system with density rho=1.2, and size Lx=3,Ly=3 (N=11 particles).  
Here the system is biased for large values of the global order parameter:
	phi = 1/N | \sum_j exp(i(\theta_j)) |,
where \theta_j is the phase of the pulsating particle j. As a control force, a global synchronizing force is considered. 
The calibration file is already provided as 'amph_curve_L0303_1.2.txt'. Results from a fresh run may be compared with the provided output files using
the provided run and cloning settings.