Segment Analysis

library(alcyon)

lineStringMap <- st_read(
    system.file(
        "extdata", "testdata", "barnsbury", "barnsbury_small_axial_original.mif",
        package = "alcyon"
    ),
    geometry_column = 1L, quiet = TRUE
)
axialShapeGraph <- as(lineStringMap, "AxialShapeGraph")
segMap <- axialToSegmentShapeGraph(
    axialShapeGraph,
    stubRemoval = 0.4
)

plot(segMap[, "Connectivity"])

segmentAnalysed <- allToAllTraverse(
    segMap,
    radii = c("n", "200"),
    radiusTraversalType = TraversalType$Metric,
    traversalType = TraversalType$Angular,
    quantizationWidth = pi / 1024,
    includeBetweenness = FALSE
)
plot(segmentAnalysed[, "T1024 Total Depth"])

segmentAnalysed <- allToAllTraverse(
    segmentAnalysed,
    radii = c("n", "100"),
    radiusTraversalType = TraversalType$Topological,
    traversalType = TraversalType$Topological,
    includeBetweenness = FALSE
)
plot(segmentAnalysed[, "Topological Total Length R100 metric"])

segmentResult <- allToAllTraverse(
    segmentAnalysed,
    radii = c("n", "200"),
    radiusTraversalType = TraversalType$Metric,
    traversalType = TraversalType$Metric,
    includeBetweenness = FALSE
)
plot(segmentResult[, "Metric Total Length R200 metric"])

segmentAnalysed <- oneToAllTraverse(
    segmentAnalysed,
    traversalType = TraversalType$Topological,
    fromX = 1217.1,
    fromY = -1977.3
)

plot(segmentAnalysed[, "Topological Step Depth"])