cenScatPlot: Scatter plot of water-quality data
In seawaveQ: SEAWAVE-Q Model

Description Usage Arguments Details Value Author(s) References Examples

Function to generate a scatter plot that indicates censored and estimated water-quality concentrations.

cenScatPlot(
  data,
  datescol = "dates",
  pname,
  qwcols = c("R", "P"),
  site = "",
  xlabel = "",
  ylabel = "Concentration",
  legpos = "topright",
  legcex = 1,
  ...
)

`data`	is the dataset with columns that begin with P followed by alphanumeric characters indicating concentration data and columns that begin with R followed by alphanumeric characters that match those of the concentration data indicating qualification codes. See example datasets for more information about the data format, see `IllRivValleyCty` and `qwMoRivOmaha`.
`datescol`	is the column label for the dates column.
`pname`	is the column heading (parameter name) for the particular water-quality constituent to be plotted (omit the starting character, for example for sulfate data indicated by P00945, enter "00945").
`qwcols`	is a character vector with the beginning of the column headers for remarks code (default is R), and beginning of column headers for concentration data (default is P for parameter).
`site`	is a label for the plot title indicating the site where the water-quality samples were collected.
`xlabel`	is the label for the x-axis, defaults to no label.
`ylabel`	is the label for the y-axis.
`legpos`	is the position of the legend, see legend.
`legcex`	is a numerical value giving the amount by which the legend text and symbols should be magnified relative to the default, 1.
`...`	arguments to be passed to plot method.

This function uses the qualification, or remark, column associated with water-quality concentration values to indicate which samples are unqualified, which are estimated, and which are censored. A blank remark field or an "_" indicates that the concentration value is not qualified; an "E" indicates the value has been estimated; and a less than symbol, "<", indicates the value has been censored as less than a minimum reporting level. See Oblinger Childress and others (1999) for information on the minimum reporting level and the definition of "E" for U.S. Geological Survey data. Other users may have a different definition of the minimum reporting level, but censored values need to be qualified with a "<". Using the "E" code is optional.

A scatter plot

Karen R. Ryberg

Oblinger Childress, C.J., Foreman, W.T., Connor, B.F., and Maloney, T.J., 1999, New reporting procedures based on long-term method detection levels and some considerations for interpretations of water-quality data provided by the U.S. Geological Survey: U.S. Geological Survey Open-File Report 99–193, 19 p., https://water.usgs.gov/owq/OFR_99-193/index.html.

data(swData)
# scatter plot of Simazine concentrations
cenScatPlot(IllRivValleyCty, pname = "04035")
# scatter plot with many additional plotting arguments
par(las = 1, tcl = 0.5)
cenScatPlot(IllRivValleyCty, pname = "04035", 
            site = "05586100 Illinois River at Valley City, IL",
            ylabel = "Simazine concentration, in micrograms per liter", 
            legcex = 0.7, ylim = c(0, 0.4), yaxs = "i", cex.lab = 0.9, 
            cex.axis = 0.9, xlim = c(as.Date("1996-01-01", "%Y-%m-%d"), 
            as.Date("2012-01-01", "%Y-%m-%d")), xaxs = "i", xaxt = "n")
axdates <- c("1996-01-01", "2000-01-01", "2004-01-01", "2008-01-01",
           "2012-01-01")
axis(1, as.Date(axdates, "%Y-%m-%d"), 
     labels = c("1996", "2000", "2004", "2008", "2012"), cex.axis = 0.9)