oce (version 0.1.63)

as.sealevel: Coerce data into sea-level dataset

Description

Coerces a dataset (minimally, a sequence of heights) into a sealevel dataset.

Usage

as.sealevel(eta,
  header="",
  start.time=as.POSIXct("2000-01-01"),
  station.number="001",
  station.version="A",
  station.name="Santa",
  region="mythical",
  year="2000",
  latitude="90000N",
  longitude="000000E",
  GMT.offset=0,
  decimation.method=1,
  reference.offset=0,
  reference.code="",
  units="MM")

Arguments

eta

A list of sea-level heights in metres, in an hourly sequence.

header

A character string as read from first line of a standard data file.

start.time

A time in POSIX format, e.g. as.POSIXct("2000-01-01")

station.number

Three-character string giving station number

station.version

Single character for version of station

station.name

Name of station (at most 18 characters)

region

Region or country of station (at most 19 characters)

year

Four-character number of year

latitude

First 2 characters are degrees of latitude, next 2 are minutes, next 2 are tenths of minutes, and last is "N" or "S" for hemisphere, e.g. "90000N". Negatives are not allowed.

longitude

First 3 characters are degrees of longitude, next 2 are minutes, next 2 are tenths of minutes, and last is "E" or "W" for hemisphere, e.g. "000000E". Negatives are not allowed.

GMT.offset

Offset from GMT. (BUG: this is ignored.)

decimation.method

1: filtered; 2: simple average of all samples; 3: spot readings; 4: other

reference.offset

?

reference.code

?

units

"MM" or "mm" if the sea-level heights are in millimetres (the default for data files). "M" or "m" if the heights are in metres.

Value

• A sealevel object.

Details

The arguments are based on the standard data format, as described at ftp://ilikai.soest.hawaii.edu/rqds/hourly.fmt.

References

ftp://ilikai.soest.hawaii.edu/rqds/hourly.fmt.

See Also

read.sealevel reads data, summary.sealevel summarizes the information, while plot.sealevel plots it.

Examples

library(oce)
h <- 1:(24*100) # fake 100 days
eta <- 1.0 * sin(2*pi*h/12.4172) + 0.8 * sin(2*pi*h/24.0)
eta <- eta + 0.1 * rnorm(length(h)) # add some noise
h <- as.sealevel(eta, units="m")
summary(h)