sectionSmooth: Smooth a section (preliminary version that may change)

Description

Smooth a section in the lateral (alpha version that may change)

Usage

sectionSmooth(section, method=c("spline", "barnes"), debug=getOption("oceDebug"), ...)

Arguments

section

a section object containing the section to be smoothed. For method="spline", the pressure levels must match for each station in the section.

method

specifies the method to use; see Details.

debug

a flag that turns on debugging. Set to 1 to get a moderate amount of debugging information, or to 2 to get more.

...

optional extra arguments, passed to either smooth.spline or interpBarnes.

Value

An object of class "section" that is smoother than the input section.

Details

This function should be used with caution, as should any operation that changes data. Although smoothing may be desirable to produce aesthetically-pleasing plots, it can also introduce artifacts that can lead to erroneous conclusions. The prudent analyst starts by comparing plots of the raw data with plots of the smoothed data. For method="spline", the section is smoothed using smooth.spline on individual pressure levels, with any parameters listed in parameters being passed to that function. If df is not present in parameters, then this function sets it to the number of stations divided by 5. Smoothing is done separately for temperature, salinity, and sigma-theta.

For the (much slower) method="barnes" method, smoothing is done across both horizontal and vertical coordinates, using interpBarnes. Any arguments in ... being passed to that function; see Examples.

Examples

Run this code

library(oce)
data(coastlineWorld)
data(a03)
gs <- sectionGrid(subset.oce(a03, indices=124:102), p=seq(0, 5000, 150))
gss1 <- sectionSmooth(gs, "spline", df=16)
plot(gss1, coastline=coastlineWorld, map.xlim=c(-80,-55))
gss2 <- sectionSmooth(gs, "barnes", xr=24, yr=100)
plot(gss2, coastline=coastlineWorld, map.xlim=c(-80,-55))