intensitynet {intensitynet}

Constructor of the class intensitynet.

Description

This constructor creates an intensitynet object using an adjacency matrix, the coordinates of the nodes and the coordinates of the events.

Usage

intensitynet(
  adjacency_mtx,
  node_coords,
  event_data,
  graph_type = c("undirected", "directed", "mixed"),
  event_correction = 5
)

Arguments

adjacency_mtx

Network adjacency matrix

node_coords

Nodes latitude and longitude matrix (coordinates)

event_data

DataFrame with event latitude and longitude coordinates (mandatory columns) and optional attributes related to the events

graph_type

Network type: 'undirected' (default), 'directed' or 'mixed'

event_correction

Value that determines how far can be an event to be considered part of a segment (default 5). This value highly depends on the given coordinate system

Value

intensitynet class object containing: graph = <igraph>, events = <matrix>, graph_type = c('directed', 'undirected', 'mixed'), distances = <matrix>, event_correction = <integer>, events_related = <boolean>

Examples

library(spatstat)
data(chicago)
chicago_df <- as.data.frame(chicago[["data"]]) # Get as dataframe the data from Chicago

# Get the adjacency matrix. One way is to create an igraph object from the edge coordinates.
edges <- cbind(chicago[["domain"]][["from"]], chicago[["domain"]][["to"]])
chicago_net <- igraph::graph_from_edgelist(edges)

# And then use the igraph function 'as_adjacency_matrix'
chicago_adj_mtx <- as.matrix(igraph::as_adjacency_matrix(chicago_net))
chicago_node_coords <- data.frame(xcoord = chicago[["domain"]][["vertices"]][["x"]], 
                                 ycoord = chicago[["domain"]][["vertices"]][["y"]])
                                  
# Create the intensitynet object, in this case will be undirected 
intnet_chicago <- intensitynet(chicago_adj_mtx, 
                               node_coords = chicago_node_coords, 
                               event_data = chicago_df)