lineReduce

Description

Reduce features in any GeoJSON object, similar to Array.reduce().

Parameters

Name	Type	Description
geojson	FeatureCollection<Lines> | Feature<Lines> | Lines | Feature<GeometryCollection> | GeometryCollection	object
callback	Function	a method that takes (previousValue, currentLine, featureIndex, multiFeatureIndex, geometryIndex)
initialValue?	Reducer	Value to use as the first argument to the first call of the callback.

Returns

Reducer The value that results from the reduction.

Examples

var multiPoly = turf.multiPolygon([
  turf.polygon([
    [
      [12, 48],
      [2, 41],
      [24, 38],
      [12, 48],
    ],
    [
      [9, 44],
      [13, 41],
      [13, 45],
      [9, 44],
    ],
  ]),
  turf.polygon([
    [
      [5, 5],
      [0, 0],
      [2, 2],
      [4, 4],
      [5, 5],
    ],
  ]),
]);

turf.lineReduce(
  multiPoly,
  function (
    previousValue,
    currentLine,
    featureIndex,
    multiFeatureIndex,
    geometryIndex,
  ) {
    //=previousValue
    //=currentLine
    //=featureIndex
    //=multiFeatureIndex
    //=geometryIndex
    return currentLine;
  },
);

Installation

$ npm install @turf/meta

import { lineReduce } from "@turf/meta";
const result = lineReduce(...);

$ npm install @turf/turf

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