@turf/idw

@turf/idw

idw

Takes a FeatureCollection of points with known value, a power parameter, a cell depth, a unit of measurement and returns a FeatureCollection of polygons in a square-grid with an interpolated value property "IDW" for each grid cell. It finds application when in need of creating a continuous surface (i.e. rainfall, temperature, chemical dispersion surface...) from a set of spatially scattered points.

Parameters

• controlPoints FeatureCollection<Point> Sampled points with known value
• valueField string GeoJSON field containing the known value to interpolate on
• b number Exponent regulating the distance-decay weighting
• cellWidth number The distance across each cell
• units [string] used in calculating cellSize, can be degrees, radians, miles, or kilometers (optional, default kilometers)

Returns FeatureCollection<Polygon> grid A grid of polygons with a property field "IDW"

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This module is part of the Turfjs project, an open source module collection dedicated to geographic algorithms. It is maintained in the Turfjs/turf repository, where you can create PRs and issues.

Installation

Install this module individually:

$ npm install @turf/idw

Or install the Turf module that includes it as a function:

$ npm install @turf/turf