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"])
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segmentAnalysed <- allToAllTraverse(
segMap,
radii = c("n", "200"),
radiusTraversalType = TraversalType$Metric,
traversalType = TraversalType$Angular,
quantizationWidth = pi / 1024,
includeBetweenness = FALSE
)
plot(segmentAnalysed[, "T1024 Total Depth"])
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segmentAnalysed <- allToAllTraverse(
segmentAnalysed,
radii = c("n", "100"),
radiusTraversalType = TraversalType$Topological,
traversalType = TraversalType$Topological,
includeBetweenness = FALSE
)
plot(segmentAnalysed[, "Topological Total Length R100 metric"])
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segmentResult <- allToAllTraverse(
segmentAnalysed,
radii = c("n", "200"),
radiusTraversalType = TraversalType$Metric,
traversalType = TraversalType$Metric,
includeBetweenness = FALSE
)
plot(segmentResult[, "Metric Total Length R200 metric"])
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segmentAnalysed <- oneToAllTraverse(
segmentAnalysed,
traversalType = TraversalType$Topological,
fromX = 1217.1,
fromY = -1977.3
)
plot(segmentAnalysed[, "Topological Step Depth"])
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segmentAnalysed <- oneToAllTraverse(
segmentAnalysed,
traversalType = TraversalType$Metric,
fromX = 1217.1,
fromY = -1977.3
)
plot(segmentAnalysed[, "Metric Step Depth"])
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segmentAnalysed <- oneToAllTraverse(
segmentAnalysed,
traversalType = TraversalType$Angular,
fromX = 1217.1,
fromY = -1977.3,
quantizationWidth = pi / 1024
)
plot(segmentAnalysed[, "Angular Step Depth"])
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segmentAnalysed <- oneToOneTraverse(
segmentAnalysed,
traversalType = TraversalType$Angular,
fromX = 1217.1,
fromY = -1977.3,
toX = 1017.8,
toY = -1699.3,
quantizationWidth = pi / 1024
)
column <- "Angular Shortest Path Angle"
plot(segmentAnalysed[, column],
col = "lightgray", reset = FALSE
)
plot(segmentAnalysed[
unlist(segmentAnalysed[column]) >= 0,
column
], lwd = 3, add = TRUE)
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segmentAnalysed <- oneToOneTraverse(
segmentAnalysed,
traversalType = TraversalType$Metric,
fromX = 1217.1,
fromY = -1977.3,
toX = 1017.8,
toY = -1699.3,
quantizationWidth = pi / 1024
)
column <- "Metric Shortest Path Distance"
plot(segmentAnalysed[, column],
col = "lightgray", reset = FALSE
)
plot(segmentAnalysed[
unlist(segmentAnalysed[column]) >= 0,
column
], lwd = 3, add = TRUE)
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segmentAnalysed <- oneToOneTraverse(
segmentAnalysed,
traversalType = TraversalType$Topological,
fromX = 1217.1,
fromY = -1977.3,
toX = 1017.8,
toY = -1699.3,
quantizationWidth = pi / 1024
)
column <- "Topological Shortest Path Depth"
plot(segmentAnalysed[, column],
col = "lightgray", reset = FALSE
)
plot(segmentAnalysed[
unlist(segmentAnalysed[column]) >= 0,
column
], lwd = 3, add = TRUE)
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