In development panel functions for use with lattice
parHandler(scheme = NULL, ...)
#related
getArgs(source = TRUE, local.resets = TRUE,
user.resets = TRUE, is.scales.lines = FALSE,
elements = NULL, ..., defaults = list(),
defaults.only = FALSE)
getPlotArgs(defaults.as = "axis.line", source = TRUE,
local.resets = TRUE, user.resets = TRUE,
elements = NULL, ..., is.scales.lines = NULL,
defaults.only = TRUE)
isGood4LOA(arg)
getArgs and getPlotArgs return lists of located
parameters/values. For example, the call
getPlotArgs(default.as = "axis.line")
returns a list containing the lattice defaults for an axis
line (alpha, col, lty and lwd) These
can then be used in combination with appropriate x and
y values in llines, or panel.lines calls.
The arguments local.resets and user.resets can
be added into the call to provide developer and user overrides.
(See note below.)
isGood4LOA returns a logical (TRUE or FALSE),
depending on the type of a supplied argument. This returns
FALSE for NULL, for all FALSE logicals, and
any arg that has previously been tagged as 'not wanted'.
parHandler returns a list a list suitable for use as
par.settings with most lattice plots.
The color scheme to apply. This can be a list of parameters to apply
or a character vector for a pre-defined scheme. Current pre-defined schemes include
'greyscale' (for black and white figures).
When recovering plot arguments
with getArgs or getPlotArgs, places to search for relevant
parameters. If supplied these would typically be vectors or lists. If vectors,
they are assumed to be col setting. If lists, they are assumed to be lists
of named parameters for inclusion. There are two cases that need to be handed
specially: (1) some sources, local.resets and/or user.resets
may contain both axis-specific and general information, e.g. For a scales list,
parameters to be applied just to the x axis in scales$x and parameters to be
applied to all scales in scales. In such cases these need to be checked in
order (see elements below.) (2) Some sources, e.g. axis scales, contain
both text and line parameters, with e.g. line settings declared as col.line,
etc., rather than col, etc., (which are intended for use with text.) When
supplied these need to be handled correctly (see is.scales.lines below).
local.resets and user.resets are intended as overrides for the code
developer and user, respectively. These can be logicals as well as vectors or lists.
If logicals they turn on/off the associated plot components (using isGood4LOA).
The check/update order is source, then source$element, then
local.reset, then local.reset$element, then user.reset, then
user.reset$element. This means that the developer always has last say regarding
the default appearance of a plot component and the user always has the very last say
from the command line if the local.reset is included as a formal argument in that plot.
When recovering arguments with getArgs or getPlotArgs,
should source be treated as a lattice scales list? If so, and source
is checked for line parameters, line-specific terms such as col.line, etc., will be
recovered as col, etc., while general terms (meant for text in scales lists)
will be ignored. (Note: getPlotArgs guesses this based on defaults.as if
not supplied.)
When recovering arguments with getArgs or getPlotArgs, this
identifies the elements in source, local.resets and user.resets that
may contain case-specific information. As with lattice handling of scales
axis-specific information in source$element(s) is assumed to take priority over
general information in source. (Note: if elements are not declared only
general/top level information in source, local.resets and user.resets
is considered at present.)
Other arguments, often ignored.
When recovering arguments with getArgs,
defaults is an optional 'fall-back' in case nothing is recovered from source,
local.resets and user.resets. defaults.only is a logical: if TRUE
only parameters named in defaults are searched for, otherwise all parameters are
recovered. With getPlotArgs, defaults.as selects an appropriate default. This
should be a trellis parameter name, e.g. 'axis.line', 'axis.text', etc. The
function uses this to identify appropriate plot parameters to search for/select, e.g.
pch, col, cex, etc for 'plot.symbol', and to identify default
values for each of these (if defaults.only = TRUE).
For isGood4LOA a plot argument that can used
to turn a plot panel or panel component on or off.
Karl Ropkins
getArgs returns a list of parameters/values based on
lattice, developer and user settings. If multiple
elements are identified as containing case-specific information,
the list will contain one list of plot parameters for each named
element.
getPlotArgs is a variation of getArgs
intended for use with panel... and l... type
lattice functions. It returns a list of plot parameters
for different plot components, e.g. symbols, lines, or text.
isGood4LOA is a simple workhorse that checks if a
supplied arg should be used by loa. (See value and
note below.)
parHandler manages the default appearance of plots.
These function makes extensive use of code developed by others.
lattice: Sarkar, Deepayan (2008) Lattice: Multivariate Data Visualization with R. Springer, New York. ISBN 978-0-387-75968-5
#getPlotArgs/isGood4LOA notes
#in formals
#my.plot <- function(..., user.reset = TRUE, ...)
#in main code body
#local.resets <- [what developer wants]
#plot.arg <- getPlotArgs("[type]", source, local.reset, user.reset)
#in panel call
#(for panel off/on control)
#if(isGood4LOA(plot.arg)) panel...(..., plot.arg,...)
#in panel... function
#for panel component off/on control)
#if(isGood4LOA(plot.arg1)) panel...(..., plot.arg1,...)
#if(isGood4LOA(plot.arg2)) l...(..., plot.arg2,...)
#etc.
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