direction_to_leader calculates the direction to the leader of each
spatiotemporal group. The function expects a data.table with relocation
data appended with a rank_position_group_direction column indicating the
ranked position along the group direction generated with
leader_direction_group(return_rank = TRUE). Relocation data should be in
two columns representing the X and Y coordinates, or in a geometry column
prepared by the helper function get_geometry().
Usage
direction_to_leader(
DT = NULL,
coords = NULL,
group = "group",
crs = NULL,
geometry = "geometry"
)Arguments
- DT
input data.table
- coords
character vector of X coordinate and Y coordinate column names. Note: the order is assumed X followed by Y column names
- group
group column name, generated by
group_pts, default 'group'- crs
numeric or character defining the coordinate reference system to be passed to sf::st_crs. For example, either
crs = "EPSG:32736"orcrs = 32736. Used only if coords are provided, see details under Interface- geometry
simple feature geometry list column name, generated by
get_geometry(). Default 'geometry', see details under Interface
Value
direction_to_leader returns the input DT appended with a
direction_leader column indicating the direction to the group leader in
radians. A value of NaN is returned when the coordinates of the focal
individual equal the coordinates of the leader.
Missing values in coordinates / geometry are ignored and NA is returned.
A message is returned when the direction_leader column already exist in
the input DT because it will be overwritten.
See details for appending outputs using modify-by-reference in the FAQ.
Details
The DT must be a data.table. If your data is a data.frame, you can
convert it by reference using data.table::setDT() or by reassigning using
data.table::data.table().
This function expects a rank_position_group_direction column generated with
leader_direction_group(return_rank = TRUE), a group column generated with
the group_pts function. The group argument expects the name of the column
in DT which correspond to the group column.
See below under "Interface" for details on providing coordinates and under "Direction function" for details on the underlying direction function used.
Interface
Two interfaces are available for providing coordinates:
Provide
coordsandcrs. Thecoordsargument expects the names of the X and Y coordinate columns. Thecrsargument expects a character string or numeric defining the coordinate reference system to be passed to sf::st_crs. For example, for UTM zone 36S (EPSG 32736), the crs argument iscrs = "EPSG:32736"orcrs = 32736. See https://spatialreference.org for a list of EPSG codes.(New!) Provide
geometry. Thegeometryargument allows the user to supply ageometrycolumn that represents the coordinates as a simple feature geometry list column. This interface expects the user to prepare their input DT withget_geometry(). To use this interface, leave thecoordsandcrsargumentsNULL, and the default argument forgeometry('geometry') will be used directly.
Direction function
The underlying distance function used depends on the crs of the coordinates or geometry provided.
If the crs is provided and longlat degrees (as determined by
sf::st_is_longlat()), the distance function islwgeom::st_geod_azimuth().If the crs is provided and not longlat degrees (eg. a projected UTM), the coordinates or geometry are transformed to
sf::st_crs(4326)before the distance is measured usinglwgeom::st_geod_azimuth().If the crs is NULL or NA_crs_, the distance function cannot be used and an error is returned.
See also
distance_to_leader, leader_direction_group, group_pts,
lwgeom::st_geod_azimuth()
Other Direction functions:
direction_group(),
direction_polarization(),
direction_step(),
direction_to_centroid(),
edge_alignment(),
edge_delay(),
edge_direction(),
edge_zones(),
leader_direction_group(),
leader_edge_delay()
Other Leadership functions:
leader_direction_group(),
leader_edge_delay()
Examples
# Load data.table
library(data.table)
# Read example data
DT <- fread(system.file("extdata", "DT.csv", package = "spatsoc"))
# (Subset example data to reduce example run time)
DT <- DT[year(datetime) == 2016]
# 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
# Spatial grouping with timegroup
group_pts(DT, threshold = 50, id = 'ID',
coords = c('X', 'Y'), timegroup = 'timegroup')
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> group
#> <int>
#> 1: 1
#> 2: 2
#> 3: 3
#> 4: 4
#> 5: 5
#> ---
#> 7288: 728
#> 7289: 729
#> 7290: 5531
#> 7291: 731
#> 7292: 5532
# Calculate direction at each step
direction_step(
DT = DT,
id = 'ID',
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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> group direction
#> <int> <units>
#> 1: 1 -2.65649015 [rad]
#> 2: 2 2.17592086 [rad]
#> 3: 3 -1.98432277 [rad]
#> 4: 4 1.90650150 [rad]
#> 5: 5 -0.04059949 [rad]
#> ---
#> 7288: 728 -2.99285448 [rad]
#> 7289: 729 -1.59174536 [rad]
#> 7290: 5531 2.36456688 [rad]
#> 7291: 731 -2.67757174 [rad]
#> 7292: 5532 NA [rad]
# Calculate group centroid
centroid_group(DT, coords = c('X', 'Y'))
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> group direction centroid_X centroid_Y
#> <int> <units> <num> <num>
#> 1: 1 -2.65649015 [rad] 715851.4 5505340
#> 2: 2 2.17592086 [rad] 715822.8 5505289
#> 3: 3 -1.98432277 [rad] 715872.9 5505252
#> 4: 4 1.90650150 [rad] 715820.5 5505231
#> 5: 5 -0.04059949 [rad] 715830.6 5505227
#> ---
#> 7288: 728 -2.99285448 [rad] 700191.6 5509089
#> 7289: 729 -1.59174536 [rad] 700156.0 5508800
#> 7290: 5531 2.36456688 [rad] 700028.7 5508826
#> 7291: 731 -2.67757174 [rad] 700254.6 5508589
#> 7292: 5532 NA [rad] 700110.1 5508383
# Calculate group direction
direction_group(DT)
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> group direction centroid_X centroid_Y group_direction
#> <int> <units> <num> <num> <units>
#> 1: 1 -2.65649015 [rad] 715851.4 5505340 -2.65649015 [rad]
#> 2: 2 2.17592086 [rad] 715822.8 5505289 2.17592086 [rad]
#> 3: 3 -1.98432277 [rad] 715872.9 5505252 -1.98432277 [rad]
#> 4: 4 1.90650150 [rad] 715820.5 5505231 1.90650150 [rad]
#> 5: 5 -0.04059949 [rad] 715830.6 5505227 -0.04059949 [rad]
#> ---
#> 7288: 728 -2.99285448 [rad] 700191.6 5509089 -3.05184005 [rad]
#> 7289: 729 -1.59174536 [rad] 700156.0 5508800 -2.41173804 [rad]
#> 7290: 5531 2.36456688 [rad] 700028.7 5508826 2.36456688 [rad]
#> 7291: 731 -2.67757174 [rad] 700254.6 5508589 -1.70798015 [rad]
#> 7292: 5532 NA [rad] 700110.1 5508383 NA [rad]
# Calculate leader in terms of position along group direction
leader_direction_group(
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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> group direction centroid_X centroid_Y group_direction
#> <int> <units> <num> <num> <units>
#> 1: 1 -2.65649015 [rad] 715851.4 5505340 -2.65649015 [rad]
#> 2: 2 2.17592086 [rad] 715822.8 5505289 2.17592086 [rad]
#> 3: 3 -1.98432277 [rad] 715872.9 5505252 -1.98432277 [rad]
#> 4: 4 1.90650150 [rad] 715820.5 5505231 1.90650150 [rad]
#> 5: 5 -0.04059949 [rad] 715830.6 5505227 -0.04059949 [rad]
#> ---
#> 7288: 728 -2.99285448 [rad] 700191.6 5509089 -3.05184005 [rad]
#> 7289: 729 -1.59174536 [rad] 700156.0 5508800 -2.41173804 [rad]
#> 7290: 5531 2.36456688 [rad] 700028.7 5508826 2.36456688 [rad]
#> 7291: 731 -2.67757174 [rad] 700254.6 5508589 -1.70798015 [rad]
#> 7292: 5532 NA [rad] 700110.1 5508383 NA [rad]
#> position_group_direction rank_position_group_direction
#> <num> <num>
#> 1: 0.00000 1
#> 2: 0.00000 1
#> 3: 0.00000 1
#> 4: 0.00000 1
#> 5: 0.00000 1
#> ---
#> 7288: -19.72453 2
#> 7289: -23.62960 5
#> 7290: 0.00000 1
#> 7291: -16.87561 5
#> 7292: 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> group direction centroid_X centroid_Y group_direction
#> <int> <units> <num> <num> <units>
#> 1: 1 -2.65649015 [rad] 715851.4 5505340 -2.65649015 [rad]
#> 2: 2 2.17592086 [rad] 715822.8 5505289 2.17592086 [rad]
#> 3: 3 -1.98432277 [rad] 715872.9 5505252 -1.98432277 [rad]
#> 4: 4 1.90650150 [rad] 715820.5 5505231 1.90650150 [rad]
#> 5: 5 -0.04059949 [rad] 715830.6 5505227 -0.04059949 [rad]
#> ---
#> 7288: 728 -2.99285448 [rad] 700191.6 5509089 -3.05184005 [rad]
#> 7289: 729 -1.59174536 [rad] 700156.0 5508800 -2.41173804 [rad]
#> 7290: 5531 2.36456688 [rad] 700028.7 5508826 2.36456688 [rad]
#> 7291: 731 -2.67757174 [rad] 700254.6 5508589 -1.70798015 [rad]
#> 7292: 5532 NA [rad] 700110.1 5508383 NA [rad]
#> position_group_direction rank_position_group_direction
#> <num> <num>
#> 1: 0.00000 1
#> 2: 0.00000 1
#> 3: 0.00000 1
#> 4: 0.00000 1
#> 5: 0.00000 1
#> ---
#> 7288: -19.72453 2
#> 7289: -23.62960 5
#> 7290: 0.00000 1
#> 7291: -16.87561 5
#> 7292: NA NA
#> 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)
#> ---
#> 7288: POINT (700211.6 5509087)
#> 7289: POINT (700165.3 5508825)
#> 7290: POINT (700028.7 5508826)
#> 7291: POINT (700230.9 5508609)
#> 7292: POINT (700110.1 5508383)
group_pts(DT, threshold = 5, id = 'ID', timegroup = 'timegroup')
#> group column will be overwritten by this function
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> direction centroid_X centroid_Y group_direction
#> <units> <num> <num> <units>
#> 1: -2.65649015 [rad] 715851.4 5505340 -2.65649015 [rad]
#> 2: 2.17592086 [rad] 715822.8 5505289 2.17592086 [rad]
#> 3: -1.98432277 [rad] 715872.9 5505252 -1.98432277 [rad]
#> 4: 1.90650150 [rad] 715820.5 5505231 1.90650150 [rad]
#> 5: -0.04059949 [rad] 715830.6 5505227 -0.04059949 [rad]
#> ---
#> 7288: -2.99285448 [rad] 700191.6 5509089 -3.05184005 [rad]
#> 7289: -1.59174536 [rad] 700156.0 5508800 -2.41173804 [rad]
#> 7290: 2.36456688 [rad] 700028.7 5508826 2.36456688 [rad]
#> 7291: -2.67757174 [rad] 700254.6 5508589 -1.70798015 [rad]
#> 7292: NA [rad] 700110.1 5508383 NA [rad]
#> position_group_direction rank_position_group_direction
#> <num> <num>
#> 1: 0.00000 1
#> 2: 0.00000 1
#> 3: 0.00000 1
#> 4: 0.00000 1
#> 5: 0.00000 1
#> ---
#> 7288: -19.72453 2
#> 7289: -23.62960 5
#> 7290: 0.00000 1
#> 7291: -16.87561 5
#> 7292: NA NA
#> geometry group
#> <sfc_POINT> <int>
#> 1: POINT (715851.4 5505340) 1
#> 2: POINT (715822.8 5505289) 2
#> 3: POINT (715872.9 5505252) 3
#> 4: POINT (715820.5 5505231) 4
#> 5: POINT (715830.6 5505227) 5
#> ---
#> 7288: POINT (700211.6 5509087) 7135
#> 7289: POINT (700165.3 5508825) 7136
#> 7290: POINT (700028.7 5508826) 7137
#> 7291: POINT (700230.9 5508609) 7138
#> 7292: POINT (700110.1 5508383) 7139
direction_step(
DT = DT,
id = 'ID'
)
#> direction column will be overwritten by this function
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> centroid_X centroid_Y group_direction position_group_direction
#> <num> <num> <units> <num>
#> 1: 715851.4 5505340 -2.65649015 [rad] 0.00000
#> 2: 715822.8 5505289 2.17592086 [rad] 0.00000
#> 3: 715872.9 5505252 -1.98432277 [rad] 0.00000
#> 4: 715820.5 5505231 1.90650150 [rad] 0.00000
#> 5: 715830.6 5505227 -0.04059949 [rad] 0.00000
#> ---
#> 7288: 700191.6 5509089 -3.05184005 [rad] -19.72453
#> 7289: 700156.0 5508800 -2.41173804 [rad] -23.62960
#> 7290: 700028.7 5508826 2.36456688 [rad] 0.00000
#> 7291: 700254.6 5508589 -1.70798015 [rad] -16.87561
#> 7292: 700110.1 5508383 NA [rad] NA
#> rank_position_group_direction geometry group
#> <num> <sfc_POINT> <int>
#> 1: 1 POINT (715851.4 5505340) 1
#> 2: 1 POINT (715822.8 5505289) 2
#> 3: 1 POINT (715872.9 5505252) 3
#> 4: 1 POINT (715820.5 5505231) 4
#> 5: 1 POINT (715830.6 5505227) 5
#> ---
#> 7288: 2 POINT (700211.6 5509087) 7135
#> 7289: 5 POINT (700165.3 5508825) 7136
#> 7290: 1 POINT (700028.7 5508826) 7137
#> 7291: 5 POINT (700230.9 5508609) 7138
#> 7292: NA POINT (700110.1 5508383) 7139
#> direction
#> <units>
#> 1: -2.65649015 [rad]
#> 2: 2.17592086 [rad]
#> 3: -1.98432277 [rad]
#> 4: 1.90650150 [rad]
#> 5: -0.04059949 [rad]
#> ---
#> 7288: -2.99285448 [rad]
#> 7289: -1.59174536 [rad]
#> 7290: 2.36456688 [rad]
#> 7291: -2.67757174 [rad]
#> 7292: NA [rad]
centroid_group(DT)
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> centroid_X centroid_Y group_direction position_group_direction
#> <num> <num> <units> <num>
#> 1: 715851.4 5505340 -2.65649015 [rad] 0.00000
#> 2: 715822.8 5505289 2.17592086 [rad] 0.00000
#> 3: 715872.9 5505252 -1.98432277 [rad] 0.00000
#> 4: 715820.5 5505231 1.90650150 [rad] 0.00000
#> 5: 715830.6 5505227 -0.04059949 [rad] 0.00000
#> ---
#> 7288: 700191.6 5509089 -3.05184005 [rad] -19.72453
#> 7289: 700156.0 5508800 -2.41173804 [rad] -23.62960
#> 7290: 700028.7 5508826 2.36456688 [rad] 0.00000
#> 7291: 700254.6 5508589 -1.70798015 [rad] -16.87561
#> 7292: 700110.1 5508383 NA [rad] NA
#> rank_position_group_direction geometry group
#> <num> <sfc_POINT> <int>
#> 1: 1 POINT (715851.4 5505340) 1
#> 2: 1 POINT (715822.8 5505289) 2
#> 3: 1 POINT (715872.9 5505252) 3
#> 4: 1 POINT (715820.5 5505231) 4
#> 5: 1 POINT (715830.6 5505227) 5
#> ---
#> 7288: 2 POINT (700211.6 5509087) 7135
#> 7289: 5 POINT (700165.3 5508825) 7136
#> 7290: 1 POINT (700028.7 5508826) 7137
#> 7291: 5 POINT (700230.9 5508609) 7138
#> 7292: NA POINT (700110.1 5508383) 7139
#> direction centroid
#> <units> <sfc_POINT>
#> 1: -2.65649015 [rad] POINT (715851.4 5505340)
#> 2: 2.17592086 [rad] POINT (715822.8 5505289)
#> 3: -1.98432277 [rad] POINT (715872.9 5505252)
#> 4: 1.90650150 [rad] POINT (715820.5 5505231)
#> 5: -0.04059949 [rad] POINT (715830.6 5505227)
#> ---
#> 7288: -2.99285448 [rad] POINT (700211.6 5509087)
#> 7289: -1.59174536 [rad] POINT (700165.3 5508825)
#> 7290: 2.36456688 [rad] POINT (700028.7 5508826)
#> 7291: -2.67757174 [rad] POINT (700230.9 5508609)
#> 7292: NA [rad] POINT (700110.1 5508383)
direction_group(DT)
#> group_direction column will be overwritten by this function
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> centroid_X centroid_Y position_group_direction
#> <num> <num> <num>
#> 1: 715851.4 5505340 0.00000
#> 2: 715822.8 5505289 0.00000
#> 3: 715872.9 5505252 0.00000
#> 4: 715820.5 5505231 0.00000
#> 5: 715830.6 5505227 0.00000
#> ---
#> 7288: 700191.6 5509089 -19.72453
#> 7289: 700156.0 5508800 -23.62960
#> 7290: 700028.7 5508826 0.00000
#> 7291: 700254.6 5508589 -16.87561
#> 7292: 700110.1 5508383 NA
#> rank_position_group_direction geometry group
#> <num> <sfc_POINT> <int>
#> 1: 1 POINT (715851.4 5505340) 1
#> 2: 1 POINT (715822.8 5505289) 2
#> 3: 1 POINT (715872.9 5505252) 3
#> 4: 1 POINT (715820.5 5505231) 4
#> 5: 1 POINT (715830.6 5505227) 5
#> ---
#> 7288: 2 POINT (700211.6 5509087) 7135
#> 7289: 5 POINT (700165.3 5508825) 7136
#> 7290: 1 POINT (700028.7 5508826) 7137
#> 7291: 5 POINT (700230.9 5508609) 7138
#> 7292: NA POINT (700110.1 5508383) 7139
#> direction centroid group_direction
#> <units> <sfc_POINT> <units>
#> 1: -2.65649015 [rad] POINT (715851.4 5505340) -2.65649015 [rad]
#> 2: 2.17592086 [rad] POINT (715822.8 5505289) 2.17592086 [rad]
#> 3: -1.98432277 [rad] POINT (715872.9 5505252) -1.98432277 [rad]
#> 4: 1.90650150 [rad] POINT (715820.5 5505231) 1.90650150 [rad]
#> 5: -0.04059949 [rad] POINT (715830.6 5505227) -0.04059949 [rad]
#> ---
#> 7288: -2.99285448 [rad] POINT (700211.6 5509087) -2.99285448 [rad]
#> 7289: -1.59174536 [rad] POINT (700165.3 5508825) -1.59174536 [rad]
#> 7290: 2.36456688 [rad] POINT (700028.7 5508826) 2.36456688 [rad]
#> 7291: -2.67757174 [rad] POINT (700230.9 5508609) -2.67757174 [rad]
#> 7292: NA [rad] POINT (700110.1 5508383) NA [rad]
leader_direction_group(
DT
)
#> position_group_direction column will be overwritten by this function
#> rank_position_group_direction column will be overwritten by this function
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> centroid_X centroid_Y geometry group direction
#> <num> <num> <sfc_POINT> <int> <units>
#> 1: 715851.4 5505340 POINT (715851.4 5505340) 1 -2.65649015 [rad]
#> 2: 715822.8 5505289 POINT (715822.8 5505289) 2 2.17592086 [rad]
#> 3: 715872.9 5505252 POINT (715872.9 5505252) 3 -1.98432277 [rad]
#> 4: 715820.5 5505231 POINT (715820.5 5505231) 4 1.90650150 [rad]
#> 5: 715830.6 5505227 POINT (715830.6 5505227) 5 -0.04059949 [rad]
#> ---
#> 7288: 700191.6 5509089 POINT (700211.6 5509087) 7135 -2.99285448 [rad]
#> 7289: 700156.0 5508800 POINT (700165.3 5508825) 7136 -1.59174536 [rad]
#> 7290: 700028.7 5508826 POINT (700028.7 5508826) 7137 2.36456688 [rad]
#> 7291: 700254.6 5508589 POINT (700230.9 5508609) 7138 -2.67757174 [rad]
#> 7292: 700110.1 5508383 POINT (700110.1 5508383) 7139 NA [rad]
#> centroid group_direction position_group_direction
#> <sfc_POINT> <units> <num>
#> 1: POINT (715851.4 5505340) -2.65649015 [rad] 0
#> 2: POINT (715822.8 5505289) 2.17592086 [rad] 0
#> 3: POINT (715872.9 5505252) -1.98432277 [rad] 0
#> 4: POINT (715820.5 5505231) 1.90650150 [rad] 0
#> 5: POINT (715830.6 5505227) -0.04059949 [rad] 0
#> ---
#> 7288: POINT (700211.6 5509087) -2.99285448 [rad] 0
#> 7289: POINT (700165.3 5508825) -1.59174536 [rad] 0
#> 7290: POINT (700028.7 5508826) 2.36456688 [rad] 0
#> 7291: POINT (700230.9 5508609) -2.67757174 [rad] 0
#> 7292: POINT (700110.1 5508383) NA [rad] NA
#> rank_position_group_direction
#> <num>
#> 1: 1
#> 2: 1
#> 3: 1
#> 4: 1
#> 5: 1
#> ---
#> 7288: 1
#> 7289: 1
#> 7290: 1
#> 7291: 1
#> 7292: NA
direction_to_leader(DT)
#> Warning: groups found missing leader (rank_position_group_direction == 1):
#> 732, 1464, 2184, 2914, 3637, 4359, 5034, 5728, 6417, 7139
#> 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
#> ---
#> 7288: J 700211.6 5509087 2016-12-31 14:00:49 1 0 728
#> 7289: J 700165.3 5508825 2016-12-31 16:00:23 1 0 729
#> 7290: J 700028.7 5508826 2016-12-31 18:00:53 1 0 730
#> 7291: J 700230.9 5508609 2016-12-31 20:00:53 1 0 731
#> 7292: J 700110.1 5508383 2016-12-31 22:00:54 1 0 732
#> centroid_X centroid_Y geometry group direction
#> <num> <num> <sfc_POINT> <int> <units>
#> 1: 715851.4 5505340 POINT (715851.4 5505340) 1 -2.65649015 [rad]
#> 2: 715822.8 5505289 POINT (715822.8 5505289) 2 2.17592086 [rad]
#> 3: 715872.9 5505252 POINT (715872.9 5505252) 3 -1.98432277 [rad]
#> 4: 715820.5 5505231 POINT (715820.5 5505231) 4 1.90650150 [rad]
#> 5: 715830.6 5505227 POINT (715830.6 5505227) 5 -0.04059949 [rad]
#> ---
#> 7288: 700191.6 5509089 POINT (700211.6 5509087) 7135 -2.99285448 [rad]
#> 7289: 700156.0 5508800 POINT (700165.3 5508825) 7136 -1.59174536 [rad]
#> 7290: 700028.7 5508826 POINT (700028.7 5508826) 7137 2.36456688 [rad]
#> 7291: 700254.6 5508589 POINT (700230.9 5508609) 7138 -2.67757174 [rad]
#> 7292: 700110.1 5508383 POINT (700110.1 5508383) 7139 NA [rad]
#> centroid group_direction position_group_direction
#> <sfc_POINT> <units> <num>
#> 1: POINT (715851.4 5505340) -2.65649015 [rad] 0
#> 2: POINT (715822.8 5505289) 2.17592086 [rad] 0
#> 3: POINT (715872.9 5505252) -1.98432277 [rad] 0
#> 4: POINT (715820.5 5505231) 1.90650150 [rad] 0
#> 5: POINT (715830.6 5505227) -0.04059949 [rad] 0
#> ---
#> 7288: POINT (700211.6 5509087) -2.99285448 [rad] 0
#> 7289: POINT (700165.3 5508825) -1.59174536 [rad] 0
#> 7290: POINT (700028.7 5508826) 2.36456688 [rad] 0
#> 7291: POINT (700230.9 5508609) -2.67757174 [rad] 0
#> 7292: POINT (700110.1 5508383) NA [rad] NA
#> rank_position_group_direction direction_leader
#> <num> <units>
#> 1: 1 NaN [rad]
#> 2: 1 NaN [rad]
#> 3: 1 NaN [rad]
#> 4: 1 NaN [rad]
#> 5: 1 NaN [rad]
#> ---
#> 7288: 1 NaN [rad]
#> 7289: 1 NaN [rad]
#> 7290: 1 NaN [rad]
#> 7291: 1 NaN [rad]
#> 7292: NA NA [rad]