impute_coords: Impute missing GPS data

In wolfeclw/circleclust: Spatiotemporal Clustering for Personal Location Data

Impute missing GPS data

Description

impute_coords() imputes missing lon/lat coordinates that occur during GPS lapses.

Usage

impute_coords(
  df,
  dt_field = NULL,
  distance_threshold = 100,
  jitter_amount = 5e-05,
  show_lapse_distance = FALSE,
  fill_open_lapses = FALSE,
  speed_threshold = NULL,
  speed_window = NULL,
  open_lapse_length = NULL
)

Arguments

df	data frame containing latitude (lat) and longitude (lon)
dt_field	character; name of datetime field.
distance_threshold	numeric; distance (meters) between the last known coordinates before GPS signal loss and the first known coordinates following signal loss are compared to this value. If the distance exceeds this threshold, coordinates are not imputed. Default = 100 meters.
jitter_amount	numeric; amount of jitter to apply to imputed coords. Default = 0.00005 decimal degrees. See st_jitter.
show_lapse_distance	logical; if TRUE, a column will be added to the output data frame listing the distance between the last and first know coordinates for each lapse in GPS signal. Default = FALSE.
fill_open_lapses	logical; if TRUE,missing coordinates at the beginning and end of the data frame are imputed (i.e. lapses not enclosed by known coordinates). Default = FALSE.
speed_threshold	numeric; criteria to impute open lapses. If the median speed (m/s) of coordinates before or after an open lapse exceeds this threshold, coordinates are not imputed.
speed_window	numeric; number of rows used to calculate speed_threshold.
open_lapse_length	numeric; if the number of rows in an open lapse exceed this threshold, coordinates are not imputed.

Value

a data frame. An additional column is created to indicate whether coordinates were imputed ('imputed_coord').

Examples

## Not run: 

impute_coords(df,
  distance_threshold = 100, jitter_amount = 0.00001, fill_open_lapses = FALSE,
  speed_threshold = NULL, speed_window = NULL, open_lapse_length = NULL
)

## End(Not run)

wolfeclw/circleclust documentation built on Aug. 13, 2024, 3:33 a.m.