R: Extract Something From an oce Object

[[,oce-method {oce} | R Documentation

## Extract Something From an oce Object

### Description

The named item is sought first in `metadata`, where an exact match to the name is required. If it is not present in the `metadata` slot, then a partial-name match is sought in the `data` slot. Failing both tests, an exact-name match is sought in a field named `dataNamesOriginal` in the object's `metadata` slot, if that field exists. Failing that, `NULL` is returned.

The full contents of the `metadata` slot of an object named `x` are returned with `x[["metadata"]]`, and `x[["data"]]` does the same thing for the data slot. Even if the full contents are not needed, this scheme can be useful in circumventing the searching scheme described in the previous paragraph, e.g. `x[["data"]]$longitude` might be used to select longitude from the data slot of `x`, as an alternative to `oceGetData(x,"longitude")`.

To get information on the specialized variants of this function, type e.g. `?"[[,adv-method"` for information on extracting data from an object of `adv-class`.

### Usage

    ## S4 method for signature 'oce'
    x[[i, j, ...]]

### Arguments

`x` | An oce object
`i` | The item to extract.
`j` | Optional additional information on the `i` item.
`...` | Optional additional information (ignored).

### Examples

    data(ctd)
    ctd[["longitude"]] # in metadata
    head(ctd[["salinity"]]) # in data
    data(section)
    summary(section[["station", 1]])

[Package oce version 1.0-1 Index]