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Version: 7.0.0



Takes a triangular plane as a Polygon and a Point within that triangle and returns the z-value at that point. The Polygon should have properties a, b, and c that define the values at its three corners. Alternatively, the z-values of each triangle point can be provided by their respective 3rd coordinate if their values are not provided as properties.


pointCoordthe Point for which a z-value will be calculated
triangleFeature<Polygon>a Polygon feature with three vertices


    number the z-value for interpolatedPoint


var point = turf.point([-75.3221, 39.529]);
// "a", "b", and "c" values represent the values of the coordinates in order.
var triangle = turf.polygon(
[-75.1221, 39.57],
[-75.58, 39.18],
[-75.97, 39.86],
[-75.1221, 39.57],
a: 11,
b: 122,
c: 44,

var zValue = turf.planepoint(point, triangle); = zValue;


$ npm install @turf/planepoint

import { planepoint } from "@turf/planepoint";
const result = planepoint(...);
$ npm install @turf/turf

import * as turf from "@turf/turf";
const result = turf.planepoint(...);