R: Report Statistics of adp or adv Velocities

velocityStatistics {oce} | R Documentation

## 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.
`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`).

### Author(s)

Dan Kelley

### See Also

Other things related to adp data: `[[,adp-method`, `[[<-,adp-method`, `ad2cpHeaderValue()`, `adp-class`, `adpEnsembleAverage()`, `adp_rdi.000`, `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`, `subtractBottomVelocity()`, `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

    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")

[Package oce version 1.2-0 Index]