Methods for constructing blurs, as used in the blur argument to
geom_blur_dots() or stat_mcse_dots().
Supports automatic partial function application.
blur_gaussian(x, r, sd)blur_interval(x, r, sd, .width = 0.95)
A vector of length x giving the opacity of the radial gradient representing
the dot at each x value.
numeric vector of positive distances from the center of the dot (assumed to be 0) to evaluate blur function at.
radius of the dot that is being blurred.
standard deviation of the dot that is being blurred.
for blur_interval(), a probability giving the width of
the interval.
These functions are passed x, r, and sd when geom_blur_dots()
draws in order to create a radial gradient representing each dot in the
dotplot. They return values between 0 and 1 giving the opacity of the
dot at each value of x.
blur_gaussian() creates a dot with radius r that has a Gaussian blur with
standard deviation sd applied to it. It does this by calculating
\(\alpha(x; r, \sigma)\), the opacity at distance \(x\) from the center
of a dot with radius \(r\) that has had a Gaussian blur with standard
deviation \(\sigma\) = sd applied to it:
$$ \alpha(x; r, \sigma) = \Phi \left(\frac{x + r}{\sigma} \right) - \Phi \left(\frac{x - r}{\sigma} \right) $$
blur_interval() creates an interval-type representation around the
dot at 50% opacity, where the interval is a Gaussian quantile interval with
mass equal to .width and standard deviation sd.
geom_blur_dots() and stat_mcse_dots() for geometries making use of
blurs.
# see examples in geom_blur_dots()
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