NonResidenceExtractId: Extract the Non-residence Events, the Corresponding Distance...

View source: R/NonResidenceExtractId.R

NonResidenceExtractIdR Documentation

Extract the Non-residence Events, the Corresponding Distance Moved and the Rate of Movement

Description

This function creates a nonresidences data frame from a residences event data frame and a optional distance matrix (sDistanceMatrix). This function is not mandatory as it is carried out automatically if the user provides a distance matrix in the sDistanceMatrix field when running the RunResidenceExtraction function.

Usage

NonResidenceExtractId(sResidenceEventFile, sDistanceMatrix = NULL)

Arguments

sResidenceEventFile

a residence event table

sDistanceMatrix

an optional two dimentional array (matrix) containing the pairwise distances between a series of receivers

Value

STARTTIME

a POSIXct vector object containing the date and time a transmitter left a receiver/station after a residence event

ENDTIME

a POSIXct vector object containing the date and time a transmitter arrived at a receiver/station and a new residence event was logged

NONRESIDENCEEVENT

a numeric vector indexing each nonresidence event

TRANSMITTERID

a numeric or character vector indexing the transmitter from which nonresidence events were determined

RECEIVERID1

a numeric or character vector indexing the receiver which the transmitter initially moved from. If STATIONNAME is specified in the function, STATIONNAME1 is returned

RECEIVERID2

a numeric or character vector indexing the receiver which the transmitter moved to. If STATIONNAME is specified in the function, STATIONNAME2 is returned

DURATION

a numeric vector containing the total time in seconds taken for the transmitter to move between two receivers or stations

DISTANCE

a numeric vector containing the minimum distance travelled in meters between two receivers/stations according to the distance matrix. If a distance matrix was not attached (=NULL), distance is returned as 0

ROM

a numeric vector containing the rate of movement (ROM) in m/s. This is calculated from the distance travelled (i.e. DISTANCE) divided by the time taken to move between the receivers (i.e. DURATION)

Author(s)

Ross Dwyer, Mathew Watts, Hamish Campbell

See Also

RunResidenceExtraction

Examples

# This function runs within the RunResidenceExtraction function when 
# a distance matrix is provided by the user.

# Extract residence events at RECEIVERS from the VTrack-transformed 
# saltwater crocodile archive

# Load the crocodile data into the VTrack archive
data(crocs)  
Vcrocs <- ReadInputData(infile=crocs,
                        iHoursToAdd=10,
                        dateformat = NULL,
                        sVemcoFormat='1.0')       

# Extract data for only the transmitter #139
T139 <- ExtractData(Vcrocs, 
                    sQueryTransmitterList = 139)

# Extract residence and non residence events using receiver data
# 	Minimum number of detections to register as a residence
# 	event = 2  
# 	Min time period between detections before residence event
# 	recorded = 43200 secs (12 hours)
#T139Res <- RunResidenceExtraction(sInputFile=T139, 
#                                 sLocation="RECEIVERID",
#                                 iResidenceThreshold=1,
#                                 iTimeThreshold=43200,
#                                 sDistanceMatrix=NULL)

# The residences event table
#T139resid <- T139Res$residences

# Generate the circuitous distance matrix
#data(PointsCircuitous_crocs)
#CircuitousDM <- GenerateCircuitousDistance(PointsCircuitous_crocs)

# Ensure there is only 1 Transmitter in dataset (if not, run the function within a loop)
#length(unique(T139resid$TRANSMITTERID))

# Run the non-residence function
#NonResidenceExtractId(sResidenceEventFile=T139resid,
#                      sDistanceMatrix=CircuitousDM)

RossDwyer/VTrack documentation built on Feb. 23, 2024, 10:40 p.m.