geo_distance_point_to_line()

Calculates the shortest distance between a coordinate and a line or multiline on Earth.

Syntax

geo_distance_point_to_line(longitude, latitude, lineString)

Arguments

  • longitude: Geospatial coordinate longitude value in degrees. Valid value is a real number and in the range [-180, +180].
  • latitude: Geospatial coordinate latitude value in degrees. Valid value is a real number and in the range [-90, +90].
  • lineString: Line or multiline in the GeoJSON format and of a dynamic data type.

Returns

The shortest distance, in meters, between a coordinate and a line or multiline on Earth. If the coordinate or lineString are invalid, the query will produce a null result.

Note

  • The geospatial coordinates are interpreted as represented by the WGS-84 coordinate reference system.
  • The geodetic datum used to measure distance on Earth is a sphere. Line edges are geodesics on the sphere.
  • If input line edges are straight cartesian lines, consider using geo_line_densify() in order to convert planar edges to geodesics.

LineString definition and constraints

dynamic({"type": "LineString","coordinates": [ [lng_1,lat_1], [lng_2,lat_2] ,..., [lng_N,lat_N] ]})

dynamic({"type": "MultiLineString","coordinates": [ [ line_1, line_2 ,..., line_N ] ]})

  • LineString coordinates array must contain at least two entries.
  • Coordinates [longitude,latitude] must be valid where longitude is a real number in the range [-180, +180] and latitude is a real number in the range [-90, +90].
  • Edge length must be less than 180 degrees. The shortest edge between the two vertices will be chosen.

Tip

  • Using literal LineString or a MultiLineString may result in better performance.
  • If you want to know the shortest distance between one or more points to many lines, consider folding these lines into one multiline. See the example below.

Examples

The following example finds the shortest distance between North Las Vegas Airport and a nearby road.

Distance between North Las Vegas Airport and road.

print distance_in_meters = geo_distance_point_to_line(-115.199625, 36.210419, dynamic({ "type":"LineString","coordinates":[[-115.115385,36.229195],[-115.136995,36.200366],[-115.140252,36.192470],[-115.143558,36.188523],[-115.144076,36.181954],[-115.154662,36.174483],[-115.166431,36.176388],[-115.183289,36.175007],[-115.192612,36.176736],[-115.202485,36.173439],[-115.225355,36.174365]]}))
distance_in_meters
3797.88887253334

Storm events in south coast US. The events are filtered by a maximum distance of 5 km from the defined shore line.

Storm events in the US south coast.

let southCoast = dynamic({"type":"LineString","coordinates":[[-97.18505859374999,25.997549919572112],[-97.58056640625,26.96124577052697],[-97.119140625,27.955591004642553],[-94.04296874999999,29.726222319395504],[-92.98828125,29.82158272057499],[-89.18701171875,29.11377539511439],[-89.384765625,30.315987718557867],[-87.5830078125,30.221101852485987],[-86.484375,30.4297295750316],[-85.1220703125,29.6880527498568],[-84.00146484374999,30.14512718337613],[-82.6611328125,28.806173508854776],[-82.81494140625,28.033197847676377],[-82.177734375,26.52956523826758],[-80.9912109375,25.20494115356912]]});
StormEvents
| project BeginLon, BeginLat, EventType
| where geo_distance_point_to_line(BeginLon, BeginLat, southCoast) < 5000
| render scatterchart with (kind=map) // map rendering available in Kusto Explorer desktop

NY taxi pickups. Pickups are filtered by maximum distance of 0.1 meters from the defined multiline.

NYC taxi pickups on Madison Ave.

let MadisonAve = dynamic({"type":"MultiLineString","coordinates":[[[-73.9879823,40.7408625],[-73.9876492,40.7413345],[-73.9874982,40.7415046],[-73.9870343,40.7421446],[-73.9865812,40.7427655],[-73.9861292,40.7433756],[-73.9856813,40.7439956],[-73.9854932,40.7442606],[-73.9852232,40.7446216],[-73.9847903,40.7452305],[-73.9846232,40.7454536],[-73.9844803,40.7456606],[-73.9843413,40.7458585],[-73.9839533,40.7463955],[-73.9839002,40.7464696],[-73.9837683,40.7466566],[-73.9834342,40.7471015],[-73.9833833,40.7471746],[-73.9829712,40.7477686],[-73.9824752,40.7484255],[-73.9820262,40.7490436],[-73.9815623,40.7496566],[-73.9811212,40.7502796],[-73.9809762,40.7504976],[-73.9806982,40.7509255],[-73.9802752,40.7515216],[-73.9798033,40.7521795],[-73.9795863,40.7524656],[-73.9793082,40.7528316],[-73.9787872,40.7534725],[-73.9783433,40.7540976],[-73.9778912,40.7547256],[-73.9774213,40.7553365],[-73.9769402,40.7559816],[-73.9764622,40.7565766],[-73.9760073,40.7572036],[-73.9755592,40.7578366],[-73.9751013,40.7584665],[-73.9746532,40.7590866],[-73.9741902,40.7597326],[-73.9737632,40.7603566],[-73.9733032,40.7609866],[-73.9728472,40.7616205],[-73.9723422,40.7622826],[-73.9718672,40.7629556],[-73.9714042,40.7635726],[-73.9709362,40.7642185],[-73.9705282,40.7647636],[-73.9704903,40.7648196],[-73.9703342,40.7650355],[-73.9701562,40.7652826],[-73.9700322,40.7654535],[-73.9695742,40.7660886],[-73.9691232,40.7667166],[-73.9686672,40.7673375],[-73.9682142,40.7679605],[-73.9677482,40.7685786],[-73.9672883,40.7692076],[-73.9668412,40.7698296],[-73.9663882,40.7704605],[-73.9659222,40.7710936],[-73.9654262,40.7717756],[-73.9649292,40.7724595],[-73.9644662,40.7730955],[-73.9640012,40.7737285],[-73.9635382,40.7743615],[-73.9630692,40.7749936],[-73.9626122,40.7756275],[-73.9621172,40.7763106],[-73.9616111,40.7769896],[-73.9611552,40.7776245],[-73.9606891,40.7782625],[-73.9602212,40.7788866],[-73.9597532,40.7795236],[-73.9595842,40.7797445],[-73.9592942,40.7801635],[-73.9591122,40.7804105],[-73.9587982,40.7808305],[-73.9582992,40.7815116],[-73.9578452,40.7821455],[-73.9573802,40.7827706],[-73.9569262,40.7833965],[-73.9564802,40.7840315],[-73.9560102,40.7846486],[-73.9555601,40.7852755],[-73.9551221,40.7859005],[-73.9546752,40.7865426],[-73.9542571,40.7871505],[-73.9541771,40.7872335],[-73.9540892,40.7873366],[-73.9536971,40.7879115],[-73.9532792,40.7884706],[-73.9532142,40.7885205],[-73.9531522,40.7885826],[-73.9527382,40.7891785],[-73.9523081,40.7897545],[-73.9518332,40.7904115],[-73.9513721,40.7910435],[-73.9509082,40.7916695],[-73.9504602,40.7922995],[-73.9499882,40.7929195],[-73.9495051,40.7936045],[-73.9490071,40.7942835],[-73.9485542,40.7949065],[-73.9480832,40.7955345],[-73.9476372,40.7961425],[-73.9471772,40.7967915],[-73.9466841,40.7974475],[-73.9453432,40.7992905],[-73.9448332,40.7999835],[-73.9443442,40.8006565],[-73.9438862,40.8012945],[-73.9434262,40.8019196],[-73.9431412,40.8023325],[-73.9429842,40.8025585],[-73.9425691,40.8031855],[-73.9424401,40.8033609],[-73.9422987,40.8035533],[-73.9422013,40.8036857],[-73.9421022,40.8038205],[-73.9420024,40.8039552],[-73.9416372,40.8044485],[-73.9411562,40.8050725],[-73.9406471,40.8057176],[-73.9401481,40.8064135],[-73.9397022,40.8070255],[-73.9394081,40.8074155],[-73.9392351,40.8076495],[-73.9387842,40.8082715],[-73.9384681,40.8087086],[-73.9383211,40.8089025],[-73.9378792,40.8095215],[-73.9374011,40.8101795],[-73.936405,40.8115707],[-73.9362328,40.8118098]],[[-73.9362328,40.8118098],[-73.9362432,40.8118567],[-73.9361239,40.8120222],[-73.9360302,40.8120805]],[[-73.9362328,40.8118098],[-73.9361571,40.8118294],[-73.9360443,40.8119993],[-73.9360302,40.8120805]],[[-73.9360302,40.8120805],[-73.9359423,40.8121378],[-73.9358551,40.8122385],[-73.9352181,40.8130815],[-73.9348702,40.8135515],[-73.9347541,40.8137145],[-73.9346332,40.8138615],[-73.9345542,40.8139595],[-73.9344981,40.8139945],[-73.9344571,40.8140165],[-73.9343962,40.8140445],[-73.9343642,40.8140585],[-73.9343081,40.8140725],[-73.9341971,40.8140895],[-73.9341041,40.8141005],[-73.9340022,40.8140965],[-73.9338442,40.8141005],[-73.9333712,40.8140895],[-73.9325541,40.8140755],[-73.9324561,40.8140705],[-73.9324022,40.8140695]],[[-73.9360302,40.8120805],[-73.93605,40.8121667],[-73.9359632,40.8122805],[-73.9353631,40.8130795],[-73.9351482,40.8133625],[-73.9350072,40.8135415],[-73.9347441,40.8139168],[-73.9346611,40.8140125],[-73.9346101,40.8140515],[-73.9345401,40.8140965],[-73.9344381,40.8141385],[-73.9343451,40.8141555],[-73.9342991,40.8141675],[-73.9341552,40.8141985],[-73.9338601,40.8141885],[-73.9333991,40.8141815],[-73.9323981,40.8141665]]]});
nyc_taxi
| project pickup_longitude, pickup_latitude
| where geo_distance_point_to_line(pickup_longitude, pickup_latitude, MadisonAve) <= 0.1
| take 100
| render scatterchart with (kind=map) // map rendering available in Kusto Explorer desktop

The following example folds many lines into one multiline and queries this multiline. The query finds all taxi pickups that happened 10km away from all roads in Manhattan.

Lines folding.

let ManhattanRoads =
    datatable(features:dynamic)
    [
        dynamic({"type":"Feature","properties":{"Label":"145thStreetBrg"},"geometry":{"type":"MultiLineString","coordinates":[[[-73.9322259,40.8194635],[-73.9323259,40.8194743],[-73.9323973,40.8194779]]]}}),
        dynamic({"type":"Feature","properties":{"Label":"W120thSt"},"geometry":{"type":"MultiLineString","coordinates":[[[-73.9619541,40.8104844],[-73.9621542,40.8105725],[-73.9630542,40.8109455],[-73.9635902,40.8111714],[-73.9639492,40.8113174],[-73.9640502,40.8113705]]]}}),
        dynamic({"type":"Feature","properties":{"Label":"1stAve"},"geometry":{"type":"MultiLineString","coordinates":[[[-73.9704124,40.748033],[-73.9702043,40.7480906],[-73.9696892,40.7487346],[-73.9695012,40.7491976],[-73.9694522,40.7493196]],[[-73.9699932,40.7488636],[-73.9694522,40.7493196]],[[-73.9694522,40.7493196],[-73.9693113,40.7494946],[-73.9688832,40.7501056],[-73.9686562,40.7504196],[-73.9684231,40.7507476],[-73.9679832,40.7513586],[-73.9678702,40.7514986]],[[-73.9676833,40.7520426],[-73.9675462,40.7522286],[-73.9673532,40.7524976],[-73.9672892,40.7525906],[-73.9672122,40.7526806]]]}})
        // ... more roads ...
    ];
let allRoads=toscalar(
    ManhattanRoads
    | project road_coordinates=features.geometry.coordinates
    | summarize make_list(road_coordinates)
    | project multipolygon = pack("type","MultiLineString", "coordinates", list_road_coordinates));
nyc_taxi
| project pickup_longitude, pickup_latitude
| where pickup_longitude != 0 and pickup_latitude != 0
| where geo_distance_point_to_line(pickup_longitude, pickup_latitude, todynamic(allRoads)) > 10000
| take 10
| render scatterchart with (kind=map)

The following example will return a null result because of the invalid LineString input.

print distance_in_meters = geo_distance_point_to_line(1,1, dynamic({ "type":"LineString"}))
distance_in_meters

The following example will return a null result because of the invalid coordinate input.

print distance_in_meters = geo_distance_point_to_line(300, 3, dynamic({ "type":"LineString","coordinates":[[1,1],[2,2]]}))
distance_in_meters