turf-isolines

turf isolines module

turf.isolines(points, z, resolution, breaks)

Takes a FeatureCollection of points with z values and an array of value breaks and generates isolines. These are commonly used to create elevation maps, but can be used for general data interpolation as well.

Parameters

| parameter | type | description | | ------------ | ----------------- | ----------------------------------------------------------- | | points | FeatureCollection | a collection containing only Features with Point geometries | | z | string | field in properties to contour | | resolution | number | | | breaks | Array. | at which to draw contours |

Example

// create random points with random
// z-values in their properties
var points = turf.random('point', 100, {
  bbox: [0, 30, 20, 50]
});
for (var i = 0; i < points.features.length; i++) {
  points.features[i].properties.z = Math.random() * 10;
}
var breaks = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
var isolined = turf.isolines(points, 'z', 15, breaks);
//=isolined

Returns FeatureCollection, isolines

Installation

Requires nodejs.

$ npm install turf-isolines

Tests

$ npm test