Usage
ad.plot1(x1, x2, xname = deparse(substitute(x1)), if.order = TRUE,
if.rsds = FALSE, ldl = NULL, ad.tol = NULL, log = FALSE, ...)
Arguments
x1
a column vector from a matrix or data frame, x1[1], ..., x1[n].
x2
another column vector from the matrix or data frame, x2[1], ..., x2[n]. x1 and x2 must be of identical length, n, where x2 is a duplicate measurement of x1.
xname
a title can be displayed with the plot and results, e.g., xname = "Cu (mg/kg)". If this field is undefined the character string for x is used as a default.
if.order
by default the analytical duplicate results are plotted in the order in which they occur in the data file, this usually corresponds to date of analysis. Alternately, setting
if.order = FALSE results in the results being plotted against the
if.rsds
by default the absolute difference between the duplicates expressed as a percentage of their mean is plotted on the y-axis. If it is required to plot the relative standard deviations (RSDs), set if.rsds = TRUE.
ldl
by default the x-axis is defined by the measurement units. If it is desired to express the duplicate means as a ratio to the lower detection limit (ldl) of the analytical procedure, then set ldl = 'ldl' in measurement units.
ad.tol
optionally a tolerance level my be provided for the maximum acceptable percent absolute relative difference between duplicates, in which case a red dotted line is added to the plot.
log
optionally the x-axis of the plot employing duplicate means may be plotted with logarithmic scaling, if so, set log = TRUE.
...
any additional arguments to be passed to the plot function for titling, etc.