mergingCycle {stopdetection}

Merging Cycle

Description

Runs the stop and merging cycle until no changes are seen or until the max number of merges are met.

Usage

mergingCycle(
  res,
  max_merges = Inf,
  thetaD = 200,
  small_track_action = "merge",
  ...
)

Arguments

res

Results data.table from stopFinder containing columns timestamp, longitude, latitude and state

max_merges

integer of maximum number of merges to perform

thetaD

how many meters away may stops be and still be merged

small_track_action

one of "merge" or "exclude" for short tracks

...

additional optional arguments passed to moveMerger including max_locs, max_time and max_dist

Value

Modifies res data.table by reference

Examples

# Load data
library(data.table)
data(loc_data_2019); setDT(loc_data_2019)
# Find initial set of stops
stopFinder(loc_data_2019, thetaD = 200, thetaT = 300)
# This selection contains two short tracks to eliminate and two stops to merge
example <- copy(loc_data_2019[state_id %between% c(1, 11)])
events_pre_merge <- returnStateEvents(example)
# Perform the merging
mergingCycle(example, thetaD = 200, small_track_action = "exclude", max_locs = Inf)
events_post_merge <- returnStateEvents(example)
# From 11 states to 8 states
events_pre_merge[, .(state_id, state, meanlat, meanlon, n_locations)]
events_post_merge[, .(state_id, state, meanlat, meanlon, n_locations)]