as.section {oce}R Documentation

Create a section

Description

Create a section based on columnar data, or a set of oce-class objects that can be coerced to CTD form with as.ctd.

Usage

as.section(salinity, temperature, pressure, longitude, latitude, station,
  sectionId="")

Arguments

salinity

This may be a numerical vector, in which case it is interpreted as the salinity, and the other arguments are used for the other components of ctd-class objects. Alternatively, it may be one of a variety of other objects from which the CTD objects can be inferred, in which case the other arguments are ignored; see ‘Details’.

temperature

Temperature, in a vector holding values for all stations.

pressure

Pressure, in a vector holding values for all stations.

longitude

Longitude, in a vector holding values for all stations.

latitude

Latitude, in a vector holding values for all stations.

station

Station identifiers, in a vector holding values for all stations.

sectionId

section identifier.

Details

If the first argument is a numerical vector, then it is taken to be the salinity, and factor is applied to station to break the data up into chunks that are assembled into ctd-class objects with as.ctd and combined to make a section-class object to be returned. This mode of operation is provided as a convenience for datasets that are already partly processed; if original CTD data are available, the next mode is preferred, because it permits the storage of much more data and metadata in the CTD object.

If the first argument is a list containing oce objects that can be coerced into CTD form with as.ctd – or a character vector containing the names of such objects that are defined in the calling environment – then those objects are combined to form the station, and all other arguments are ignored. This is the best way to call as.section.

If the first argument is a argo-class object, then the profiles it contains are turned into ctd-class object, and these are assembled into a section to be returned.

Value

An object of class "section".

Author(s)

Dan Kelley

See Also

The documentation for section-class explains the structure of section objects, and outlines other functions dealing with them.

Examples

library(oce)
data(ctd)
## vector of names of CTD objects
fake <- ctd
fake[["temperature"]] <- ctd[["temperature"]] + 0.5
fake[["salinity"]] <- ctd[["salinity"]] + 0.1
fake[["longitude"]] <- ctd[["longitude"]] + 0.01
fake[["station"]] <- "fake"
sec1 <- as.section(c("ctd", "fake"))
summary(sec1)
## vector of CTD objects
ctds <- vector("list", 2)
ctds[[1]] <- ctd
ctds[[2]] <- fake
sec2 <- as.section(ctds)
summary(sec2)
## argo data (a subset)
data(argo)
sec3 <- as.section(subset(argo, profile<5))
summary(sec3)

[Package oce version 0.9-18 Index]