*** This is a file for Sam and Chris to share R code ***
Singles-species file consists of:
i. r-K logistic model, where b and d are linear functions of N
ii. r-K logistic model, where b and d are non-linear functions of N
Two-species file consists of:
i. r-K logistic model with mutualism, varying coefficients, N, and K
ii. a simple example of plotting a vector field with nullclines and some trajectories