section-class {oce} | R Documentation

## Class to store hydrographic section data

### Description

Class to store hydrographic section data, with standard slots `metadata`, `data` and `processingLog`.

### Methods

The examples given below use `s` to represent the name of a section.

#### Extracting values

A `list` of stations is retrieved by `s[["station"]]`. Individual stations are retrieved by providing a station number as a second argument in the index, e.g. the first station is `s[["station", 1]]` (which is a `ctd-class` object).

Aggregated values of the quantities measured at each level of the CTD profiles contained within the section may be accessed as e.g. `section[["salinity"]]`. This works for any quantity whose name is present in the constituent profiles.

Since it is often useful to pair such quantities with locations, `section[["longitude"]]` and `section[["latitude"]]` return vectors with values repeated for each level in each CTD (see the `pairs()` call in the example section). If just one latitude or longitude is desired per station, e.g. `section[["latitude", "byStation"]]` may be used. Station-by-station values of dynamic height are provided by e.g. `section[["dynamic height"]]`. The depths (actually pressures) of all data are obtained from e.g. `section[["depth"]]`, and the distances along the transect (measured from the first station) are obtained from e.g. `section[["distance"]]`.

#### Assigning values

(This feature has yet to be added.)

#### Overview of contents

The `show` method (e.g. `show(section)`) displays information about the object.

### Author(s)

Dan Kelley

### See Also

Sections can be read with `read.section` or created with `read.section` or created from CTD objects by using `as.section` or by adding a ctd station to an existing section with `sectionAddStation`.

Sections may be sorted with `sectionSort`, subsetted with `subset.section`, smoothed with `sectionSmooth`, and gridded with `sectionGrid`. Gridded sections may be plotted with `plot.section`.

Statistical summaries are provided by `summary.section`, while overviews are provided by `show.section`.

The sample dataset `section` contains data along WOCE line A03.

### Examples

    library(oce)
    data(section)
    plot(section[['station', 1]])
    pairs(cbind(z=-section[["pressure"]],T=section[["temperature"]],S=section[["salinity"]]))
    ## T profiles for first few stations in section, at common scale
    par(mfrow=c(3,3))
    Tlim <- range(section[["temperature"]])
    ylim <- rev(range(section[["pressure"]]))
    for (stn in section[["station",1:9]])
    plotProfile(stn, xtype='temperature', ylim=ylim, Tlim=Tlim)

[Package oce version 0.9-18 Index]