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Version: 7.2.0

flattenReduce

描述​

¥Description

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

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

参数​

¥Parameters

名称类型描述
geojsonFeatureCollection | 特性 | GeometryObject | GeometryCollection | 特性<GeometryCollection>任意 GeoJSON 对象
callbackflattenReduceCallback一个方法，该方法接受 (previousValue, currentFeature, featureIndex, multiFeatureIndex)
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 features = turf.featureCollection([
  turf.point([26, 37], { foo: "bar" }),
  turf.multiPoint(
    [
      [40, 30],
      [36, 53],
    ],
    { hello: "world" },
  ),
]);

turf.flattenReduce(
  features,
  function (previousValue, currentFeature, featureIndex, multiFeatureIndex) {
    //=previousValue
    //=currentFeature
    //=featureIndex
    //=multiFeatureIndex
    return currentFeature;
  },
);

安装​

¥Installation

$ npm install @turf/meta

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

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