dodgr_to_sfc: dodgr_to_sfc

Description Usage Arguments Value Note Examples

Description

Convert a dodgr graph into a list composed of two objects: dat, a data.frame; and geometry, an sfc object from the (sf) package. Works by aggregating edges into LINESTRING objects representing longest sequences between all junction nodes. The resultant objects will generally contain more LINESTRING objects than the original sf object, because the former will be bisected at every junction point.

Usage

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dodgr_to_sfc(graph)

Arguments

graph

A dodgr graph

Value

A list containing (1) A data.frame of data associated with the sf geometries; and (ii) A Simple Features Collection (sfc) list of LINESTRING objects.

Note

The output of this function corresponds to the edges obtained from dodgr_contract_graph. This function does not require the sf package to be installed; the corresponding function that creates a full sf object - dodgr_to_sf does requires sf to be installed.

Examples

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hw <- weight_streetnet (hampi)
nrow(hw)
xy <- dodgr_to_sfc (hw)
dim (hw) # 5.845 edges
length (xy$geometry) # more linestrings aggregated from those edges
nrow (hampi) # than the 191 linestrings in original sf object
dim (xy$dat) # same number of rows as there are geometries
# The dodgr_to_sf function then just implements this final conversion:
# sf::st_sf (xy$dat, geometry = xy$geometry, crs = 4326)

dodgr documentation built on Aug. 8, 2021, 1:06 a.m.