lhov: Hovmöller diagram for lisst objects

In AlexCast/lisst: Functions for manipulation of the Laser In-Situ Scattering and Transmissometry (LISST) data

Description

Create Hovmöller diagram for lisst objects based on sample number, measurement time or depth.

Usage

lhov(
  x,
  by = "sample",
  norm = TRUE,
  legend = TRUE,
  total = TRUE,
  col,
  xlab,
  ylab,
  zlab,
  yu,
  zu,
  brks
)

Arguments

x	A lisst object.
by	Ordinate axis dimension. Must be one of 'sample', 'time' or 'depth'.
norm	Logic. Should the magnitude values de normalized? See details.
legend	Logic. Should a legend be added to the plot?
total	Logic. Should an upper pannel with the total magnitude be added?
col	A color pallete to be used. If not specified a default pallete will be used.
yu	The units for the abscissa. See details.
zu	The units for the magnitude values. See details.
brks	Passed to lstat function. See ?lstat for details.

Details

The abscissa of the Hovmöller diagram will show the ring number if data is 'raw' or 'cor' and the median angle or size of the bin, as appropriate for the lisst object type.

The z scale is provided in log10 for appropriate color mapping. However, LISST SOP will return 0 volume concentration if concentration is below 0.001 ppm. In that case, zeros as treated as half this minimum value, 0.0005 ppm for ploting purposes only.

If the lisst object is not regularly spaced in the chosen dimension, it will be binned for raster representation. The nbins parameter will control the number of bins, with all bins having the same interval size. The sample dimension will always be regular.

Normalization is performed by the sum of all detector values. It is provided to aid visual separation from changes in concentration and distribution. If TRUE a top pannel is added to the plot, with a line plot indicating the magnitude of the sum of detector values.

If legend is set to TRUE a bottom pannel will be added to the plot with a magnitude scale. The axis label and units are affected by the zlab and zu parameters.

Note that unit conversion is performed 'automatcaly' using the units package. If there is no standard conversion between the default and the request units the function will exit with an error. See link{units} for details.

Examples

flp <- system.file("extdata", "DN_27_rs.asc", package = "lisst")
model <- "100CX" 
lop <- read_lisst(flp, model = model)
lhov(lop, by = 'sample')
lhov(lop, by = 'sample', norm = FALSE)
lhov(lop, by = 'sample', norm = FALSE, legend = FALSE)

AlexCast/lisst documentation built on July 17, 2021, 12:58 a.m.