Generate a dyad ID for edge-list generated by edge_nn or
edge_dist.
Value
dyad_id returns the input data.table with appended "dyadID"
column.
See details for appending outputs using modify-by-reference in the FAQ.
Details
An undirected edge identifier between, for example individuals A and B will be A-B (and reverse B and A will be A-B). Internally sorts and pastes id columns.
More details in the edge and dyad vignette (in progress).
Examples
# Load data.table
library(data.table)
# Read example data
DT <- fread(system.file("extdata", "DT.csv", package = "spatsoc"))
# Cast the character column to POSIXct
DT[, datetime := as.POSIXct(datetime, tz = 'UTC')]
#> ID X Y datetime population
#> <char> <num> <num> <POSc> <int>
#> 1: A 715851.4 5505340 2016-11-01 00:00:54 1
#> 2: A 715822.8 5505289 2016-11-01 02:01:22 1
#> 3: A 715872.9 5505252 2016-11-01 04:01:24 1
#> 4: A 715820.5 5505231 2016-11-01 06:01:05 1
#> 5: A 715830.6 5505227 2016-11-01 08:01:11 1
#> ---
#> 14293: J 700616.5 5509069 2017-02-28 14:00:54 1
#> 14294: J 700622.6 5509065 2017-02-28 16:00:11 1
#> 14295: J 700657.5 5509277 2017-02-28 18:00:55 1
#> 14296: J 700610.3 5509269 2017-02-28 20:00:48 1
#> 14297: J 700744.0 5508782 2017-02-28 22:00:39 1
# Temporal grouping
group_times(DT, datetime = 'datetime', threshold = '20 minutes')
#> ID X Y datetime population minutes timegroup
#> <char> <num> <num> <POSc> <int> <int> <int>
#> 1: A 715851.4 5505340 2016-11-01 00:00:54 1 0 1
#> 2: A 715822.8 5505289 2016-11-01 02:01:22 1 0 2
#> 3: A 715872.9 5505252 2016-11-01 04:01:24 1 0 3
#> 4: A 715820.5 5505231 2016-11-01 06:01:05 1 0 4
#> 5: A 715830.6 5505227 2016-11-01 08:01:11 1 0 5
#> ---
#> 14293: J 700616.5 5509069 2017-02-28 14:00:54 1 0 1393
#> 14294: J 700622.6 5509065 2017-02-28 16:00:11 1 0 1394
#> 14295: J 700657.5 5509277 2017-02-28 18:00:55 1 0 1440
#> 14296: J 700610.3 5509269 2017-02-28 20:00:48 1 0 1395
#> 14297: J 700744.0 5508782 2017-02-28 22:00:39 1 0 1396
# Edge-list generation
edges <- edge_dist(
DT,
threshold = 100,
id = 'ID',
coords = c('X', 'Y'),
timegroup = 'timegroup',
returnDist = TRUE,
fillNA = TRUE
)
# Generate dyad IDs
dyad_id(edges, 'ID1', 'ID2')
#> Key: <timegroup, ID1>
#> timegroup ID1 ID2 distance dyadID
#> <int> <char> <char> <num> <char>
#> 1: 1 A <NA> NA <NA>
#> 2: 1 B G 5.782904 B-G
#> 3: 1 C <NA> NA <NA>
#> 4: 1 D <NA> NA <NA>
#> 5: 1 E H 65.061671 E-H
#> ---
#> 22985: 1440 G <NA> NA <NA>
#> 22986: 1440 H <NA> NA <NA>
#> 22987: 1440 I C 2.831071 C-I
#> 22988: 1440 I F 7.512922 F-I
#> 22989: 1440 J <NA> NA <NA>
# Or, using the new geometry interface
get_geometry(DT, coords = c('X', 'Y'), crs = 32736)
#> ID X Y datetime population minutes timegroup
#> <char> <num> <num> <POSc> <int> <int> <int>
#> 1: A 715851.4 5505340 2016-11-01 00:00:54 1 0 1
#> 2: A 715822.8 5505289 2016-11-01 02:01:22 1 0 2
#> 3: A 715872.9 5505252 2016-11-01 04:01:24 1 0 3
#> 4: A 715820.5 5505231 2016-11-01 06:01:05 1 0 4
#> 5: A 715830.6 5505227 2016-11-01 08:01:11 1 0 5
#> ---
#> 14293: J 700616.5 5509069 2017-02-28 14:00:54 1 0 1393
#> 14294: J 700622.6 5509065 2017-02-28 16:00:11 1 0 1394
#> 14295: J 700657.5 5509277 2017-02-28 18:00:55 1 0 1440
#> 14296: J 700610.3 5509269 2017-02-28 20:00:48 1 0 1395
#> 14297: J 700744.0 5508782 2017-02-28 22:00:39 1 0 1396
#> geometry
#> <sfc_POINT>
#> 1: POINT (715851.4 5505340)
#> 2: POINT (715822.8 5505289)
#> 3: POINT (715872.9 5505252)
#> 4: POINT (715820.5 5505231)
#> 5: POINT (715830.6 5505227)
#> ---
#> 14293: POINT (700616.5 5509069)
#> 14294: POINT (700622.6 5509065)
#> 14295: POINT (700657.5 5509277)
#> 14296: POINT (700610.3 5509269)
#> 14297: POINT (700744 5508782)
edges <- edge_dist(DT, threshold = 100, id = 'ID', timegroup = 'timegroup')
dyad_id(edges, id = 'ID1', id2 = 'ID2')
#> Key: <timegroup, ID1>
#> timegroup ID1 ID2 dyadID
#> <int> <char> <char> <char>
#> 1: 1 A <NA> <NA>
#> 2: 1 B G B-G
#> 3: 1 C <NA> <NA>
#> 4: 1 D <NA> <NA>
#> 5: 1 E H E-H
#> ---
#> 22985: 1440 G <NA> <NA>
#> 22986: 1440 H <NA> <NA>
#> 22987: 1440 I C C-I
#> 22988: 1440 I F F-I
#> 22989: 1440 J <NA> <NA>