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    haversine-calculator

    1.0.3 • Public • Published

    Haversine Calculator

    This is a simple module to help you determine the great-circle distance between two points on a sphere given their longitudes and latitudes o a geojson file.

    The formula

    This uses the ‘haversine’ formula to calculate the great-circle distance between two points – that is, the shortest distance over the earth’s surface – giving an ‘as-the-crow-flies’ distance between the points (ignoring any hills they fly over, of course!).

    Haversine: a = sin²(Δφ/2) + cos φ1 ⋅ cos φ2 ⋅ sin²(Δλ/2) c

    formula: c = 2 ⋅ atan2( √a, √(1−a) ) d = R ⋅ c

    where φ is latitude, λ is longitude, R is earth’s radius (mean radius = 6,371km); The angles need to be in radians to pass to trig functions.

    Installation

    `$ npm install haversine-calculator

    Usage of this module

    haversine (start, end, options)

    const haversineCalculator = require('haversine-calculator')
    
    const start = {
      latitude: -23.754842,
      longitude: -46.676781
    }
    
    const end = {
      latitude: -23.549588,
      longitude: -46.693210
    }
    
    console.log(haversineCalculator(start, end))
    console.log(haversineCalculator(start, end, {unit: 'meter'}))
    console.log(haversineCalculator(start, end, {unit: 'mile'}))
    console.log(haversineCalculator(start, end, {threshold: 1}))
    console.log(haversineCalculator(start, end, {threshold: 1, unit: 'meter'}))
    console.log(haversineCalculator(start, end, {threshold: 1, unit: 'mile'}))
    

    The api

    • options.unit - Unit of measurement applied to result (default km, available km, mile, meter, nmi)
    • options.threshold - If passed, will result in library returning boolean value of whether or not the start and end points are within that supplied threshold. (default null)
    • options.format - The format of start and end coordinate arguments. See the table below for available values. (default null)
    Format Example
    undefined (default) { latitude: -23.754842, longitude: -46.676781] }
    [lat,lon] [-23.754842, -46.676781]
    [lon,lat] [-23.754842, -46.676781]
    {lat,lon} { lat: -23.754842, lon: -46.676781] }
    geojson { type: 'Feature', geometry: { coordinates: [-23.754842, -46.676781] } }

    MIT License

    Install

    npm i haversine-calculator

    DownloadsWeekly Downloads

    25

    Version

    1.0.3

    License

    MIT

    Unpacked Size

    7.26 kB

    Total Files

    6

    Last publish

    Collaborators

    • jilvanpinheiro