oce (version 0.8-6)

adv-class: Class to store acoustic Doppler velocimeter data

Description

Class to store acoustic Doppler velocimeter data, holding the three standard slots used in all objects in Oce. The metadata slot contains various items relating to the dataset, including source file name, sampling rate, velocity resolution and scale, etc. The processingLog is in standard form and needs little comment. The data slot holds a numeric matrix v of velocities in m/s, with the first index indicating time and the second indicating beam number. The meanings of the beams depends on whether the object is in beam coordinates, frame coordinates, or earth coordinates. The data slot also contains identically-dimensioned raw matrices a and q, holding measures of signal strength and data quality quality, respectively. It also contains a series of vectors, e.g. time, temperature and pressure, etc., depending on what sensors are included in the package. For all of these quantities, the details can be different for different instrument types, and it is assumed that the user will be familiar with the details.

Methods

Extracting values{Data may be accessed as e.g. for an object named d, the velocity matrix is retrieved by d[["v"]], the amplitude matrix by d[["a"]], the data-quality matrix by d[["q"]], etc. (The last two can be retrieved in numerical form, as opposed to raw form, by e.g. d[["a", "numeric"]].) Similarly, the vector quantities can be retrieved by name, e.g. d[["heading"]] (or "headingSlow", if appropriate), etc.}

Assigning values{This follows the standard form, e.g. to increase all velocity data by 1 cm/s, use d[["v"]] <- 0.01 + d[["v"]].}

Overview of contents{The show method (e.g. show(d)) displays information about an ADV object named d.}

See Also

A file containing ADV data is usually recognized by Oce, and so read.oce will usually read the data. If not, one may use the general ADV function read.adv or specialized variants read.adv.nortek, read.adv.sontek.adr or read.adv.sontek.text.

ADV data may be plotted with plot.adv function, which is a generic function so it may be called simply as plot.

Statistical summaries of ADV data are provided by the generic function summary, while briefer overviews are provided with show.

Conversion from beam to xyz coordinates may be done with beamToXyzAdv, and from xyz to enu (east north up) may be done with xyzToEnuAdv. toEnuAdv may be used to transfer either beam or xyz to enu. Enu may be converted to other coordinates (e.g. aligned with a coastline) with enuToOtherAdv.