Creates a nodes-by-edges matrix that will be used by aem() of the package
adespatial. This function creates the same output as aem.build.binary()
of the package adespatial but works in a different way: it's only based on
node labels (not on coordinates). Also, this function adds labels to nodes
and edges.
nodes_by_edges_matrix(edges)a data.frame with the following two columns: from (the
first node of the edge) and to (the second node of the edge).
A list of two elements:
se.mat: the nodes-by-edges matrix of dimensions n x k, where n is
the number of nodes and k the number of edges (including the edge
between the fictitious origin and the first site);
edges: a data.frame of edge list.
library("chessboard")
# Two-dimensional sampling ----
sites_infos <- expand.grid("transect" = 1:3, "quadrat" = 1:5)
sites_infos
#> transect quadrat
#> 1 1 1
#> 2 2 1
#> 3 3 1
#> 4 1 2
#> 5 2 2
#> 6 3 2
#> 7 1 3
#> 8 2 3
#> 9 3 3
#> 10 1 4
#> 11 2 4
#> 12 3 4
#> 13 1 5
#> 14 2 5
#> 15 3 5
nodes <- create_node_labels(data = sites_infos,
transect = "transect",
quadrat = "quadrat")
edges <- create_edge_list(nodes, method = "pawn", directed = TRUE)
# Create nodes-by-edges matrix ----
nodes_by_edges_matrix(edges)
#> $se.mat
#> E-01 E-02 E-03 E-04 E-05 E-06 E-07 E-08 E-09 E-10 E-11 E-12 E-13 E-14 E-15
#> 1-1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
#> 1-2 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0
#> 1-3 1 0 0 1 1 0 0 0 0 0 0 0 0 0 0
#> 1-4 1 0 0 1 1 1 0 0 0 0 0 0 0 0 0
#> 1-5 1 0 0 1 1 1 1 0 0 0 0 0 0 0 0
#> 2-1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
#> 2-2 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0
#> 2-3 0 1 0 0 0 0 0 1 1 0 0 0 0 0 0
#> 2-4 0 1 0 0 0 0 0 1 1 1 0 0 0 0 0
#> 2-5 0 1 0 0 0 0 0 1 1 1 1 0 0 0 0
#> 3-1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
#> 3-2 0 0 1 0 0 0 0 0 0 0 0 1 0 0 0
#> 3-3 0 0 1 0 0 0 0 0 0 0 0 1 1 0 0
#> 3-4 0 0 1 0 0 0 0 0 0 0 0 1 1 1 0
#> 3-5 0 0 1 0 0 0 0 0 0 0 0 1 1 1 1
#>
#> $edges
#> from to
#> E-01 0 1-1
#> E-02 0 2-1
#> E-03 0 3-1
#> E-04 1-1 1-2
#> E-05 1-2 1-3
#> E-06 1-3 1-4
#> E-07 1-4 1-5
#> E-08 2-1 2-2
#> E-09 2-2 2-3
#> E-10 2-3 2-4
#> E-11 2-4 2-5
#> E-12 3-1 3-2
#> E-13 3-2 3-3
#> E-14 3-3 3-4
#> E-15 3-4 3-5
#>