Description:

The complete code and simulation results for finding the optimal treatment of a population front, to slow its propagation to a speed v. The algorithm is described in the paper "Optimizing strategies for slowing the spread of invasive species" by Adam Lampert (PLOS Computational Biology, DOI: 10.1371/journal.pcbi.1011996). Some of the results are demonstrated in Figs. 2-5 in that paper.

Authorship:

The code was written by Adam Lampert, Institute of Environmental Sciences, Robert H. Smith Faculty of Agriculture, Food and Environment, the Hebrew University of Jerusalem, Israel.

Installation:

Running the Matlab code requires the installation of Matlab 2021b for Windows (or a similar version of Matlab).

Running the code – general model:

1. Extract all files from "general_model_code.zip" into a single folder.

2. Open "main.m" and "calc_cost.m" using Matlab.

3. Change the parameter values, run "main.m," and wait until Matlab completes the execution.

Running the code – spongy moth model:

1. Extract all files from "spongy_moth_model_code.zip" into a single folder.

2. Open "main_F2.m" using Matlab.

3. Change the parameter values run the code, and wait until Matlab completes the execution.

Description of the data files:

The results for the general model's simulations are given as raw data in the folder "general_model_simulation_results.zip". The data files can be accessed with Matlab. Some of these results are demonstrated in the main article, Fig. 4. The results for the spongy moth model simulations are given as raw data in the folder "spongy_moth_model_simulation_results.zip". The data files can be accessed with Matlab. Some of these results are demonstrated in the main article, Fig. 5.

Each data file in "general_model_simulation_results.zip" and in "spongy_moth_model_simulation_results.zip" includes the simulation results for a given set of parameters. The name of the file specifies the parameter values used. Specifically, for the general model, the file name indicates the values of α and v used for the simulation. For the spongy moth model, the file name indicates first the value of (kλ₀) and then the values of v used for the simulation.

Each data file includes the following variables:

• n_front: an array that includes the value of the population front (n-opt) as a function of the location (x).
• treatment: an array that includes the value of the optimal treatment (A-opt) as a function of the location (x).
• Nx: size of the n_front and the treatment arrays.

The general model data files also cinclude the following parameter value:

• Dt: time resolution (Δt)

Spongy moth model data files also include the following parameter values:

• num_moves: number of spatial steps the front moves per time unit (equivalent to v).
• delta: the spatial resolution (σ).
• lambda: the parameter λ₀.