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Version: 7.2.0

lineReduce

描述​

¥Description

减少任何 GeoJSON 对象中的要素，类似于 Array.reduce()。

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

参数​

¥Parameters

名称类型描述
geojsonFeatureCollection<行数> | 特性<行数> | 行数 | 特性<GeometryCollection> | GeometryCollectionobject
callback函数一个方法，该方法接受 (previousValue, currentLine, featureIndex, multiFeatureIndex, geomationIndex)
initialValue?Reducer用作回调函数首次调用的第一个参数的值。

返回​

¥Returns

Reducer 简化后的值。

¥Reducer The value that results from the reduction.

示例​

¥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;
  },
);

安装​

¥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(...);