voronoif

Draw Voronoi cell boundaries with a hatched fill — useful for marking a region (for example a selected set of points) without obscuring layers underneath.

Based on: a custom Jarvis-PLOT renderer built on scipy.spatial.Voronoi (no direct Matplotlib equivalent).

Axes: rectangular (ax).

Coordinates

Key	Required	Meaning
x	yes	Generator point x
y	yes	Generator point y

Style

Key	Type	Purpose
where	bool array	Restrict to cells where the mask is true
hatch	string	Hatch pattern, e.g. "//", "xx"
edgecolor	color	Boundary color
facecolor	color	Fill color (often "none" to show only hatching)
linewidth	float	Boundary width
alpha	0–1	Opacity
zorder	number	Draw order

Example

- name: marked
  data:
    - source: df
  axes: ax
  method: voronoif
  coordinates:
    x: {expr: xx}
    y: {expr: yy}
  style:
    hatch: "//"
    edgecolor: black
    facecolor: none
    linewidth: 0.3

Notes

• voronoif requires scipy.
• For colored cells driven by a value, use voronoi with a z coordinate.

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See also: Plot Methods index · voronoi