| as.section {oce} | R Documentation |
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. A requirement for this
to work is that every element of the list contains both longitude
and latitude in either the metadata or data slot (in
the latter case, the mean value is recorded in the section object)
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.
as.section(salinity, temperature, pressure, longitude, latitude, station, sectionId = "")
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
|
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. |
An object of section-class.
Dan Kelley
Other things related to section data: [[,section-method,
[[<-,section-method,
handleFlags,section-method,
initializeFlagScheme,section-method,
plot,section-method,
read.section, section-class,
sectionAddStation,
sectionGrid, sectionSmooth,
sectionSort, section,
subset,section-method,
summary,section-method
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)