tagtools (version 0.2.0)

depth_rate: Estimate the vertical velocity

Description

This function is used to estimate the vertical velocity by differentiating a depth or altitude time series. A low-pass filter reduces the sensor noise that is amplified by the differentiation.

Usage

depth_rate(p, fs, fc, depth)

Value

v, The vertical velocity with the same sampling rate as p. v is a vector with the same dimensions as p. The unit of v depends on the unit of p. For example, if p is in meters, v is in meters/second

Arguments

p

A vector of depth or altitude data, or an animaltags list object containing depth or altitude data.

fs

(required only if p is a vector) is the sampling rate of p in Hz.

fc

(optional) A smoothing filter cut-off frequency in Hz. If fc is not given, a default value is used of 0.2 Hz (5 second time constant).

depth

(optional) The behavior of animals. Required only if dealing with animals not behave descent but ascent.

Examples

v <- depth_rate(p = beaked_whale$P)
plott_base(list(beaked_whale$P$data, v),
  fs = beaked_whale$P$sampling_rate,
  r = c(1, 0), panel_labels = c("Depth\n(m)", "Vertical Velocity\n(m/s)")
)