oce (version 0.9-20)

as.section: Create a Section

Description

Create a section based on columnar data, or a set of oce-class objects that can be coerced to a section. There are three cases.

Case 1. 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.

Case 2. If the first argument is a list containing oce objects, then those objects are taken as profiles of something. The only requirement for this to work are that every element of the list must contain both longitude and latitude in its metadata slot and that every element also contains pressure in its data slot.

Case 3. If the first argument is a argo-class object, then the profiles it contains are turned into ctd-class objects, and these are assembled into a section to be returned.

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.

Value

An object of section-class.

See Also

Other things related to section data: [[,section-method, [[<-,section-method, handleFlags,section-method, plot,section-method, read.section, section-class, sectionAddStation, sectionGrid, sectionSmooth, sectionSort, section, subset,section-method, summary,section-method

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)