adjustAxisLabelMargins() R function from [jamba]

Adjust axis label margins

Adjust axis label margins to accommodate axis labels


adjustAxisLabelMargins(
  x,
  margin = 1,
  maxFig = 1/2,
  cex = graphics::par("cex"),
  cex.axis = graphics::par("cex.axis"),
  prefix = "-- -- ",
  ...
)

Arguments

x: character vector of axis labels
margin: integer value indicating which margin to adjust, using the order by graphics::par("mar"), 1=bottom, 2=left, 3=top, 4=right.
maxFig: numeric fraction less than 1, indicating the maximum size of margin relative to the figure size. Setting margins too large results in an error otherwise.
cex: numeric or NULL, default graphics::par("cex"), used as a convenience with cex * cex.axis passed to graphics::strwidth(). However, graphics::axis() itself should use cex.axis when adjusting axis label font size.
cex.axis: numeric, default graphics::par("cex.axis") to define the axis label font size.
prefix: character string to add whitespace around the axis label in order to add a "buffer" of whitespace.
...: additional parameters are ignored.

Returns

list named "mai" suitable for use in graphics::par()

to adjust margin size using in inches.

Details

This function takes a vector of axis labels, and the margin where they will be used, and adjusts the relevant axis margin to accomodate the label size, up to a maximum fraction of the figure size as defined by maxFig.

Labels are assumed to be perpendicular to the axis, for example argument las=2 when using graphics::text().

Note this function does not render labels in the figure, and therefore does not revert axis margins to their original size. That process should be performed separately.

Examples


xlabs <- paste0("item_", (1:20));
ylabs <- paste0("rownum_", (1:20));

# proper adjustment should be done using withr, for example
x_cex <- 0.8;
y_cex <- 1.2;
withr::with_par(adjustAxisLabelMargins(xlabs, 1, cex.axis=x_cex), {
   withr::local_par(adjustAxisLabelMargins(ylabs, 2, cex.axis=y_cex))
   nullPlot(xlim=c(1,20), ylim=c(1,20), doMargins=FALSE);
   graphics::axis(1, at=1:20, labels=xlabs, las=2, cex.axis=x_cex);
   graphics::axis(2, at=1:20, labels=ylabs, las=2, cex.axis=y_cex);
})

withr::with_par(adjustAxisLabelMargins(xlabs, 3, cex.axis=x_cex), {
   withr::local_par(adjustAxisLabelMargins(ylabs, 4, cex.axis=y_cex))
   nullPlot(xlim=c(1,20), ylim=c(1,20), doMargins=FALSE);
   graphics::axis(3, at=1:20, labels=xlabs, las=2);
   graphics::axis(4, at=1:20, labels=ylabs, las=2);
})

par("mar")

adjustAxisLabelMargins function