Xtract -- FORTRAN code for the extraction of social interaction functions in a simple case

This program implements the method presented in the article
R. Escobedo, V. Lecheval, V. Papaspyros, F. Bonnet, F. Mondada, C. Sire and G. Theraulaz.

We include four files:
- 2hemigr.dat: the data from real fish experiments with pairs of H. rhodostomus,
- 2zebraf.dat: the data from real fish experiments with pairs of D. rerio.

The program extracts the functions f(x) and g(y) from the equation f(x)g(y) = a(x,y), where a(x,y) is given by data in three different cases:
- Case 1.1. For data homogeneously distributed (eps = 1; see the main program and the article of reference)
- Case 1.2. For data distributed as in real fish experiments (data borrowed from the experiments used in the article and in [Calovi2018]).
- Case 2. From real data of fish experiments, H. rhodostomus (2hemigr.dat) or D. rerio (2zebraf.dat).

Data files have 5 columns structured in events (Ne = number of events):
event_id || fish_id || time || x(t) || y(t)
To select an option, edit the file xtract.f and choose the corresponding value of the variable IOP (lines 93--95):
- IOP = 1: Case 1.1: analytical & homogeneous,
- IOP = 2: Case 1.2: analytical & real distribution,
- IOP = 3: Case 2: from experimental data.

[Calovi2018]: Disentangling and modeling interactions in fish with burst-and-coast swimming reveal distinct alignment and attraction behaviors, Calovi DS, Litchinko A, Lecheval V, Lopez U, Pérez Escudero A, et al. (2018). PLOS Computational Biology 14(1): e1005933. https://doi.org/10.1371/journal.pcbi.1005933

## Getting Started
### Prerequisites
A fortran compiler supporting Fortran 90 and gnuplot for visualisation.

### Installing
Download all files in the same directory.Compile with:
> gfortran -O2 xtract.f -o dale

## Running the tests
Run with:
> dale
Plot the result (i.e., the interaction functions) with:
> gnuplot
## Authors
- Ramón Escobedo - escobedor@gmail.com

## License