fill

Fill the polygon defined by a sequence of (x, y) vertices. Use it for shaded regions whose outline you describe directly.

Matplotlib: Axes.fill. Coordinates are forwarded as fill(x, y, ...).

Axes: rectangular (ax) and ternary (axtri).

Coordinates

Key	Required	Meaning
x	yes	Polygon vertex x positions (in order around the boundary)
y	yes	Polygon vertex y positions

Style

Key	Type	Purpose
facecolor / color	color	Fill color
edgecolor	color	Outline color
linewidth	float	Outline width
alpha	0–1	Opacity
hatch	string	Hatch pattern, e.g. "//", "xx"
label	string	Legend label
zorder	number	Draw order

Any other Axes.fill keyword is also accepted.

Example

- name: allowed_region
  data:
    - source: region_boundary       # ordered vertices of the closed region
  axes: ax
  method: fill
  coordinates:
    x: {expr: x}
    y: {expr: y}
  style:
    facecolor: "#cce5ff"
    edgecolor: blue
    alpha: 0.4
    zorder: 2

Notes

• The vertices must be ordered around the boundary; the polygon is closed automatically.
• To fill the band between two curves instead of a closed outline, use fill_between.

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See also: Plot Methods index · fill_between · plot