To guide a reader in quantifying the slope of components of an x-y graph, a "slope rose" is helpful.
Several radiating lines are drawn, each marked with a numerical slope. A suitable choice of slopes
is made automatically, based on the x- and y- scale of the plot.
Usage
add_slope_rose(
P,
x = NULL,
y = NULL,
scale = 1/4,
color = "red",
keepers = c("both", "pos", "neg")
)
add_violin_ruler(
P,
x = NULL,
y = NULL,
width = 1/10,
ticks = seq(0, 1, by = 0.1),
...
)
Value
A ggplot graphics object
Arguments
P
a ggplot2 object made by the ggplot2 or ggformula packages
x
the x-position of the rose. This will be assigned automatically if x isn't specified.
y
the y-position of the rose, just like x.
scale
the size of the rose as a fraction of the plot area covered (default 1/4)
color
text string (e.g. "blue") for the rose
keepers
whether to show "both" positive and negative slopes or just show the "pos" or the "neg"
width
for rulers, the distance between tick marks (in native units, where
categories are separated by a distance of 1.)
ticks
Integers, typically 0:5, that label the ticks.
...
additional graphical parameters, e.g. color = "blue"
Details
For the ruler, x gives the position of the root of the ruler, with
the rest of the ruler moving off to the left. (For vertically oriented rulers, use
a negative width.)