sc_arc: Arc-node topology.

In mdsumner/sc: Common Forms for Complex Hierarchical and Relational Data Structures

Arc-node topology.

Description

Return a label and vertex count of each arc.

Usage

sc_arc(x, ...)

## Default S3 method:
sc_arc(x, ...)

## S3 method for class 'ARC'
sc_arc(x, ...)

Arguments

x	input object
...	arguments for methods

Details

Arcs are unbranched paths within the line segment graph. Nodes are the vertices where three or more arcs meet.

As with the PATH and SC models the arc id values will only be relevant when those entities are identified and labelled. Running sc_arc on a simple features model (for example) will identify them and return a summary, but without having any record of what they refer to. Use ARC(x) first to work with models that don't included labels.

Value

a data frame with only the identities of the shared boundaries (arcs)

Examples

sc_arc(minimal_mesh)
ARC(minimal_mesh)[["arc"]]

arc <- ARC(minimal_mesh)
plot(arc)
points(arc$vertex[match(sc_node(arc)$vertex_, arc$vertex$vertex_), c("x_", "y_")])

arc <- ARC(polymesh)
plot(arc)
title("arcs and nodes")
points(arc$vertex[match(sc_node(arc)$vertex_, arc$vertex$vertex_), c("x_", "y_")])

mdsumner/sc documentation built on Jan. 16, 2024, 2:03 a.m.