displacement: Calculate Displacement of Spatial Locations

In nyu-mhealth/Mobility: Tools for Understanding Mobility Data

Description

This function calculates the distance between two consecutive stay events using their geolocations.

Usage

displacement(df, coor = NULL, groupvar = NULL)

Arguments

df	a data frame object.
coor	longitude and latitude of the spatial points in the format of c("lon","lat").
groupvar	grouping object to stratify time objects. Recommend to be ID for each individual. If groupvar is not specified, the entire data frame will be considered as one group to calculate displacement.

Value

a list of distance values. Unit is meters.

Examples

data(mobility)
mobility_stay<- stayevent(mobility, coor = c("lon","lat"), time = "datetime", dist.threshold = 100,
time.threshold = 30, time.units = "mins", groupvar = "id")
mobility_stay<- aggregate(cbind(id, stayeventlon, stayeventlat)~stayeventgroup, mobility_stay, mean)
mobility_stay$dispm<- displacement(mobility_stay, coor = c("stayeventlon","stayeventlat"), groupvar = "id")

nyu-mhealth/Mobility documentation built on Feb. 24, 2020, 10:37 p.m.