Contour

Add a contour line figure to the chart.

fig_contour(
  g,
  ...,
  sync = TRUE,
  data = NULL,
  inherit_asp = TRUE,
  colors = NULL,
  nlevels = 10,
  binwidth,
  levels,
  criticalRatio = 5,
  type = c("line", "filled")
)

Arguments

g	An object of class g2r or g2Proxy as returned by g2() or g2_proxy().
...	Options to pass to the figure, including asp(), and adjust(), active(), selected(), and config(), other key value pairs of are passed to style.
sync	Whether to sync the axis data (align) with that used in other figures, set to FALSE to not sync or set to a character string to use as name of sync group.
data	A dataset (data.frame or tibble) to use to draw the figure.
inherit_asp	Whether to inherit the aspects paseed to g2() initialisation function.
colors	A palette of colors to define the stroke of each path.
nlevels	Passed to contoureR::getContourLines. An integer number of bins to split the data into iff ‘levels’ or ‘binwidth’ have not been specified.
binwidth	Passed to contoureR::getContourLines. The desired width of the bins, if specified, will override ‘nlevels’.
levels	Passed to contoureR::getContourLines. A numeric vector of the explicitly specified levels (zvalues) to contour, by specifying this argument, it will override ‘nlevels’ and/or ‘binwidth’. If this argument is provided, the stacking order of the contours will be preserved in the order of first occurence within the supplied vector.
criticalRatio	Passed to contoureR::getContourLines. When producing the Delaunay Mesh, the quality of the mesh can be poor in the proximity to the convex hull, Del's that have an aspect ratio greater than this value are not considered when producing the contours. In this context, the aspect ratio is defined as the circumradius to twice its inradius, equilateral triangles have an aspect ratio of 1, everything else is larger.
type	Whether to draw the lines or polygons.

Details

Requires the x, y and z aspects, the width of the error bars can be changed with the size aspect.

Examples

data(volcano)

x <- 1:nrow(volcano)
y <- 1:ncol(volcano)
df <- expand.grid(x = x, y = y)
df$z <- apply(df, 1, function(x) {
  volcano[x[1], x[2]]
})

g <- g2(df, asp(x, y, z = z))

fig_contour(g)

fig_contour(g, colors = c("red", "blue"))

fig_contour(g, type = "filled", colors = c("darkblue", "white"))