`jpcontour`

Draw contour lines directly from scattered (x, y, z) points. Jarvis-PLOT interpolates the points onto a regular grid internally, then contours it — so you do not need a separate gridding/interpolation transform.

Based on: Axes.contour, preceded by a scattered-data interpolation step. Rendered in axes-fraction space so the geometry stays stable under log-scaled axes.

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

Coordinates

Key	Required	Meaning
`x`	yes	Scattered point x
`y`	yes	Scattered point y
`z`	yes	Scattered point value to contour

Style

Interpolation is configured under style.interp:

`interp` key	Default	Purpose
`method`	`natural_neighbor`	Interpolation backend
`bin`	grid default	Interpolation grid resolution
`nx` / `ny`	from `bin`	Explicit grid resolution per axis
`xlim` / `ylim`	axis limits	Interpolation extent
`nan_policy`	`strict`	`strict` leaves the convex-hull exterior empty

Plus the usual contour styling (same as contour): levels, colors, linewidths, linestyles, cmap, and the credible-region keys (contour_mode, masses, sigma, ndof, labels).

Example

- name: contours
  data:
    - source: df
  axes: ax
  method: jpcontour
  coordinates:
    x: {expr: xx}
    y: {expr: yy}
    z: {expr: LogL}
  style:
    interp: {method: natural_neighbor, bin: 300}
    levels: 10
    colors: [black]
    linewidths: [0.4]

Notes

Non-finite z regions stay masked (left blank) rather than interpolated across.
If you already have a gridded field, use plain contour instead.

See also: Plot Methods index · jpcontourf · jpfield · contour