hydroloom (version 1.1.0)

make_node_topology: Make Node Topology from Edge Topology

Description

creates a node topology table from an edge topology

Usage

make_node_topology(x, add_div = NULL, add = TRUE)
# S3 method for data.frame
make_node_topology(x, add_div = NULL, add = TRUE)
# S3 method for hy
make_node_topology(x, add_div = NULL, add = TRUE)

Value

data.frame containing id, fromnode, and tonode attributes or all attributes provided with id, fromnode and tonode in the first three columns.

If add_div is TRUE, will also add a divergence attribute where the provided diverted paths are assigned value 2, existing main paths that emanate from a divergence are assigned value 1, and all other paths are assigned value 0.

Arguments

x

data.frame network compatible with hydroloom_names.

add_div

data.frame of logical containing id and toid diverted paths to add. Should have id and toid fields. If TRUE, the network will be interpreted as a directed acyclic graph with downstream divergences included in the edge topology.

add

logical if TRUE, node topology will be added to x in return.

Examples

x <- sf::read_sf(system.file("extdata/new_hope.gpkg", package = "hydroloom"))

y <- dplyr::select(add_toids(x), -ToNode, -FromNode)

y <- make_node_topology(y)

# just the divergences which have unique fromids in x but don't in new hope.
div <- add_toids(dplyr::select(x, COMID, FromNode, ToNode),
                 return_dendritic = FALSE)
div <- div[div$toid %in%
           x$COMID[x$Divergence == 2],]

y <- dplyr::select(add_toids(x), -ToNode, -FromNode)

y <- make_node_topology(y, add_div = div)