R: Class to Store adv Data

adv-class {oce} | R Documentation

## Class to Store adv Data

### Description

This class holds data from acoustic-Doppler velocimeters.

### Details

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-method()` function, which is a generic function so it may be called simply as `plot(x)`, where `x` is an adv object.

Statistical summaries of ADV data are provided by the generic function `summary,adv-method()`.

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()`.

### Slots

`data`

  As with all `oce` objects, the `data` slot for `adv` objects is a list containing the main data for the object. The key items stored in this slot include `time` and `v`.

`metadata`

  As with all `oce` objects, the `metadata` slot for `adv` objects is a list containing information about the `data` or about the object itself. Examples that are of common interest include `frequency`, `oceCordinate`, and `frequency`.

`processingLog`

  As with all `oce` objects, the `processingLog` slot for `adv` objects is a list with entries describing the creation and evolution of the object. The contents are updated by various `oce` functions to keep a record of processing steps. Object summaries and `processingLogShow()` both display the log.

### Modifying slot contents

Although the `[[<-` operator may permit modification of the contents of adv objects (see `[[<-,adv-method`), it is better to use `oceSetData()` and `oceSetMetadata()`, because those functions save an entry in the `processingLog` that describes the change.

### Retrieving slot contents

The full contents of the `data` and `metadata` slots of a adv object may be retrieved in the standard R way using `slot()`. For example `slot(o,"data")` returns the `data` slot of an object named `o`, and similarly `slot(o,"metadata")` returns the `metadata` slot.

The slots may also be obtained with the `[[,adv-method` operator, as e.g. `o[["data"]]` and `o[["metadata"]]`, respectively.

The `[[,adv-method` operator can also be used to retrieve items from within the `data` and `metadata` slots. For example, `o[["temperature"]]` can be used to retrieve temperature from an object containing that quantity. The rule is that a named quantity is sought first within the object's `metadata` slot, with the `data` slot being checked only if `metadata` does not contain the item. This `[[` method can also be used to get certain derived quantities, if the object contains sufficient information to calculate them. For example, an object that holds (practical) salinity, temperature and pressure, along with longitude and latitude, has sufficient information to compute Absolute Salinity, and so `o[["SA"]]` will yield the calculated Absolute Salinity.

It is also possible to find items more directly, using `oceGetData()` and `oceGetMetadata()`, but neither of these functions can retrieve derived items.

### See Also

Other classes provided by oce: `adp-class`, `argo-class`, `bremen-class`, `cm-class`, `coastline-class`, `ctd-class`, `lisst-class`, `lobo-class`, `met-class`, `oce-class`, `odf-class`, `rsk-class`, `sealevel-class`, `section-class`, `topo-class`, `windrose-class`, `xbt-class`

Other things related to adv data: `[[,adv-method`, `[[<-,adv-method`, `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()`, `velocityStatistics()`, `xyzToEnuAdv()`, `xyzToEnu()`

### Examples

    data(adv)
    adv[["v"]] <- 0.001 + adv[["v"]] # add 1mm/s to all velocity components

[Package oce version 1.2-0 Index]