Nostalgic Pickled Mango

    sgeo

    0.0.6 • Public • Published

    Spherical coordinate library

    This library lets you compute distance, bearing, interpolations (mid points), and many other functions from a set of latitude / longitude pairs. Original code comes from http://www.movable-type.co.uk/scripts/latlong.html by Chris Veness

    Installation

    npm install sgeo
    

    Usage

    parseDMS

    Parses string representing degrees/minutes/seconds into numeric degrees.

    This is very flexible on formats, allowing signed decimal degrees, or deg-min-sec optionally suffixed by compass direction (NSEW). A variety of separators are accepted (eg 3º 37' 09"W) or fixed-width format without separators (eg 0033709W). Seconds and minutes may be omitted. (Note minimal validation is done).

    var sgeo = require('sgeo');
    
    var lat = sgeo.parseDMS('51 28 40.12 N');
    var lon = sgeo.parseDMS('00 00 05.31 W');

    toDMS

    Convert decimal degrees to deg/min/sec format.

    degree, prime, double-prime symbols are added, but sign is discarded, though no compass direction is added

    var dms = sgeo.toDMS(12.34544, 'dms', 2);
    

    latlon

    Provides various functionalities for geodesy calculations.

    Initializing coordinates

    var sgeo = require('sgeo');
    var p1 = new sgeo.latlon(51.0, -5.5);
    var p2 = new sgeo.latlon(58.4778, -3.01);
    
    console.log(p1.lat); //display latitude
    console.log(p1.lng); //display longitude
    console.log(p1); //toString()

    Calculate distance (in km)

    var dist = p1.distanceTo(p2);      
    console.log(dist);
    846.6
    

    Calculate bearing (in degress clockwise from north 0 - 360)

    var brng = p1.bearingTo(p2);       
    console.log(brng);
    9.871855132189069
    

    Calculate midpoint

    var pm = p1.midpointTo(p2);       
    console.log(pm);
    { lat: 54.74522196955371, lng: -4.3700915168517 }
    

    midpoint of multiple locations

    var pm = sgeo.migpoint([p1, p2, p3]);
    console.log(pm);

    Interpolate points between p1 and p2

    var inp = p1.interpolate(p2, 5);
    console.dir(inp);
    [ { lat: 51, lng: -5.499999999999999 },
      { lat: 52.87394889826373, lng: -4.959445475316697 },
      { lat: 54.74522196955371, lng: -4.370091516851731 },
      { lat: 56.613360847919104, lng: -3.7236677522713766 },
      { lat: 58.47780000000001, lng: -3.0099999999999985 } ]
    
    

    latlon.finalBeearingTo

    Returns final bearing arriving at supplied destination point from this point; the final bearing will differ from the initial bearing by varying degrees according to distance and latitude

    latlon.destinationPoint

    Returns the destination point from this point having traveled the given distance (in km) on the given initial bearing (bearing may vary before destination is reached)

    latlon.intersection

    Returns the point of intersection of two paths defined by point and bearing

    latlon.rhumbDistanceTo

    Returns the distance from this point to the supplied point, in km, travelling along a rhumb line

    latlon.rhumbBearingTo

    Returns the bearing from this point to the supplied point along a rhumb line, in degrees

    latlon.rhumbDestinationPoint

    Returns the destination point from this point having traveled the given distance (in km) on the given bearing along a rhumb line

    latlon.rhumbMidpointTo

    Returns the loxodromic midpoint (along a rhumb line) between this point and the supplied point.

    sgeo.toLat

    Convert numeric degrees to deg/min/sec latitude (suffixed with N/S)

    sgeo.toLon

    Convert numeric degrees to deg/min/sec longitude (suffixed with E/W)

    sgeo.toBrng

    Convert numeric degrees to deg/min/sec as a bearing

    Attribution

    Most of the code was originally written by Chris Veness at http://www.movable-type.co.uk/scripts/latlong.html

    Install

    npm i sgeo

    DownloadsWeekly Downloads

    33

    Version

    0.0.6

    License

    Creative Commons

    Unpacked Size

    31.9 kB

    Total Files

    4

    Last publish

    Collaborators

    • soichih