Find time cues for dives — find

This function is used to find the time cues for the start and end of either dives in a depth record or flights in an altitude record.

Usage

find_dives(p, mindepth, sampling_rate = NULL, surface = 1, findall = 0)

Arguments

p: A depth or altitude time series (a sensor data list or a vector) in meters.
mindepth: The threshold in meters at which to recognize a dive or flight. Dives shallow or flights lower than mindepth will be ignored.
sampling_rate: The sampling rate of the sensor data in Hz (samples per second).
surface: (optional) The threshold in meters at which the animal is presumed to have reached the surface. Default value is 1. A smaller value can be used if the dive/altitude data are very accurate and you need to detect shallow dives/flights.
findall: (optional) When TRUE, forces the algorithm to include incomplete dives at the start and end of the record. Default is FALSE which only recognizes complete dives.

Value

dives is a data frame with one row for each dive/flight found. The columns of dives are: start (time in seconds of the start of each dive/flight), end (time in seconds of the start of each dive/flight), max (maximum depth/altitude reached in each dive/flight), tmax (time in seconds at which the animal reaches the max depth/altitude).

Examples

BW <- beaked_whale
dives <- find_dives(p = BW$P$data, 
sampling_rate = BW$P$sampling_rate, 
mindepth = 25, surface = 5, 
findall = FALSE)