ahn_gen {AnimalHabitatNetwork} R Documentation

## Generate networks characterising habitat physical configurations

### Description

Generate undirected networks (weighted or unweighted, connected or disconnected) characterising the physical attributes and spatial organizations (or distributions) of habitat components (i.e. habitat configurations).

### Usage

```ahn_gen(N, L, mu, lamda, Connected = TRUE, Weighted = TRUE, eta = 1,
A = 25, X = NULL, Y = NULL, U = NULL, V = NULL)
```

### Arguments

 `N` The number of nodes `L` A side length of the rectangle landscape within which nodes are anchored `mu` the critical `Dij` (i.e. Euclidean distance between node `i` and `j`) at which the link removing probability curve `P(Dij, mu, lamda)` transits from concave to convex (see `ahn_prob`) `lamda` the steepness of the link removing probability curve `P(Dij, mu, lamda)`, see `ahn_prob` `Connected` `TRUE` for connected while `FALSE` ignores whether the networks are connected or not `Weighted` `TRUE` for weighted while `FALSE` for unweighted networks `eta` mediates the weight, i.e. `(Dij)^-eta`, of the link rewiring node `i` from one network component and node `j` from another network component (`i` and `j` are with an Euclidean distance of `Dij`) when the network becomes disconnected after removing links from the initial complete network with the probability `P(Dij, mu, lamda) = [1 + exp(-lamda(Dij - mu))]^-1` when both `Connected = TRUE` and `Weighted = TRUE` `A` The area of the rectangle landscape within which the network is defined `X` A vector of `X` coordinates for the `N` nodes (sampled from `[0, L]` uniformly at random if `NULL`) `Y` A vector of `Y` coordinates for the `N` nodes (sampled from `[0, A/L]` uniformly at random if `NULL`) `U` A vector with `N` elements specifying node attributes (qualitative or quantitive), by default `NULL` `V` A vector with `N` elements specifying node attributes (qualitative or quantitive), by default `NULL`

### Value

Return an animal habitat network (an `igraph` object)

### Examples

```# generate a connected and weighted network
ahn_gen(N = 10, L = 5, mu = 1, lamda = 5)

N <- 10
x <- runif(N, 0, 5)
ql <- sample(LETTERS, N, replace = TRUE)
qn <- sample(1:20, N, replace = TRUE)

# specify the X coordinates, node attributes U and V for a connected and unweighted network
ahn_gen(N, L = 5, mu = 1, lamda = 5, Weighted = FALSE, X = x, U = ql, V = qn)

# specify the Y coordinates, node attributes U and V for a weighted network, no matter if the
# network will be connected or not
ahn_gen(N, L = 5, mu = 1, lamda = 5, Weighted = TRUE, Connected = FALSE, Y = x, U = ql, V = qn)

```

[Package AnimalHabitatNetwork version 0.1.0 Index]