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"])

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

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

segmentAnalysed <- oneToAllTraverse(
  segmentAnalysed,
  traversalType = TraversalType$Angular,
  fromX = 1217.1,
  fromY = -1977.3,
  quantizationWidth = pi / 1024
)

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