oce (version 1.1-1)

velocityStatistics: Report Statistics of adp or adv Velocities

Description

Report statistics of ADP or ADV velocities, such as means and variance ellipses.

Usage

velocityStatistics(x, control, ...)

Arguments

x

an adp or adv object, i.e. one inheriting from adp-class or adv-class.

control

An optional list used to specify more information. This is presently ignored for adv objects. For adp objects, if control$bin is an integer, it is taken as the bin to be selected (otherwise, an average across bins is used).

…

additional arguments that are used in the call to mean.

Value

A list containing items the major and minor axes of the covariance ellipse (ellipseMajor and ellipseMinor), the angle of the major axis anticlockwise of the horizontal axis (ellipseAngle), and the x and y components of the mean velocity (uMean and vMean).

See Also

Other things related to adp data: [[,adp-method, [[<-,adp-method, ad2cpHeaderValue, adp-class, adpEnsembleAverage, adp, as.adp, beamName, beamToXyzAdpAD2CP, beamToXyzAdp, beamToXyzAdv, beamToXyz, beamUnspreadAdp, binmapAdp, enuToOtherAdp, enuToOther, handleFlags,adp-method, is.ad2cp, plot,adp-method, read.adp.ad2cp, read.adp.nortek, read.adp.rdi, read.adp.sontek.serial, read.adp.sontek, read.adp, read.aquadoppHR, read.aquadoppProfiler, read.aquadopp, rotateAboutZ, setFlags,adp-method, subset,adp-method, summary,adp-method, toEnuAdp, toEnu, xyzToEnuAdpAD2CP, xyzToEnuAdp, xyzToEnu

Other things related to adv data: [[,adv-method, [[<-,adv-method, adv-class, adv, beamName, beamToXyz, enuToOtherAdv, enuToOther, plot,adv-method, read.adv.nortek, read.adv.sontek.adr, read.adv.sontek.serial, read.adv.sontek.text, read.adv, rotateAboutZ, subset,adv-method, summary,adv-method, toEnuAdv, toEnu, xyzToEnuAdv, xyzToEnu

Examples

# NOT RUN {
library(oce)
data(adp)
a <- velocityStatistics(adp)
print(a)
t <- seq(0, 2*pi, length.out=100)
theta <- a$ellipseAngle * pi / 180
y <- a$ellipseMajor * cos(t) * sin(theta) + a$ellipseMinor * sin(t) * cos(theta)
x <- a$ellipseMajor * cos(t) * cos(theta) - a$ellipseMinor * sin(t) * sin(theta)
plot(adp, which="uv+ellipse+arrow")
lines(x, y, col='blue', lty="dashed", lwd=5)
arrows(0, 0, a$uMean, a$vMean, lwd=5, length=1/10, col='blue', lty="dashed")

# }