View Source Geocalc (Geocalc v0.8.5)
Calculate distance, bearing and more between Latitude/Longitude points.
Link to this section Summary
Functions
Calculates how far the point is along a path from from start-point, heading towards end-point.
Calculate the given area surface.
Check if a point is at the border of area.
Check if a point at the center point of area.
Calculates bearing.
Calculates a bounding box around a point with a radius in meters.
Calculates a bounding box for a list of points.
Returns true if the bounding box contains the given point.
Compute distance from the point to great circle defined by start-point and end-point.
Calculates the pair of meridians at which a great circle defined by two points crosses the given latitude.
Converts degrees to radians.
Finds point between start and end points in direction to end point with given distance (in meters).
Calculates distance between 2 points.
Extend the bounds to contain the given bounds.
Compute the geographic center (aka geographic midpoint, center of gravity) for an array of geocoded objects and/or [lat,lon] arrays (can be mixed).
Check if a point is inside area.
Finds intersection point from start points with given bearings.
Returns true if the bounding box intersects the given bounds.
Calculates maximum latitude reached when travelling on a great circle on given bearing from the point (Clairaut's formula). Negate the result for the minimum latitude (in the Southern hemisphere).
Check if a point is outside area.
Returns true if the bounding box overlaps the given bounds.
Converts radians to degrees.
Calculates if a point is within a polygon.
Calculates if a point is within radius of the center of a circle.
Link to this section Types
@type point_or_bearing() :: Geocalc.Point.t() | number()
Link to this section Functions
@spec along_track_distance_to(Geocalc.Point.t(), Geocalc.Point.t(), Geocalc.Point.t()) :: number()
Calculates how far the point is along a path from from start-point, heading towards end-point.
That is, if a perpendicular is drawn from the point to the (great circle) path, the along-track distance is the distance from the start point to where the perpendicular crosses the path.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> london = [51.5286416, -0.1015987]
iex> paris = [48.8588589, 2.3475569]
iex> Geocalc.along_track_distance_to(berlin, london, paris)
310412.6031976226@spec area_size( Geocalc.Shape.Circle.t() | Geocalc.Shape.Rectangle.t() | Geocalc.Shape.Ellipse.t() ) :: non_neg_integer()
Calculate the given area surface.
Returns area surface in square meters.
examples
Examples
iex> area = %Geocalc.Shape.Circle{latitude: 48.856614, longitude: 2.3522219, radius: 1000}
iex> Geocalc.area_size(area)
3141592.653589793@spec at_area_border?( Geocalc.Shape.Circle.t() | Geocalc.Shape.Rectangle.t() | Geocalc.Shape.Ellipse.t(), Geocalc.Point.t() ) :: boolean()
Check if a point is at the border of area.
Returns true if at border, false if not.
examples
Examples
iex> area = %Geocalc.Shape.Circle{latitude: 48.856614, longitude: 2.3522219, radius: 1000}
iex> point = %{lat: 48.856418, lng: 2.365871}
iex> Geocalc.at_area_border?(area, point)
true@spec at_center_point?( Geocalc.Shape.Circle.t() | Geocalc.Shape.Rectangle.t() | Geocalc.Shape.Ellipse.t(), Geocalc.Point.t() ) :: boolean()
Check if a point at the center point of area.
Returns true if at center point, false if not
examples
Examples
iex> area = %Geocalc.Shape.Circle{latitude: 48.856614, longitude: 2.3522219, radius: 100}
iex> point = %{lat: 48.856614, lng: 2.3522219}
iex> Geocalc.at_center_point?(area, point)
true@spec bearing(Geocalc.Point.t(), Geocalc.Point.t()) :: number()
Calculates bearing.
Returns radians.
examples
Examples
iex> berlin = {52.5075419, 13.4251364}
iex> paris = {48.8588589, 2.3475569}
iex> Geocalc.bearing(berlin, paris)
-1.9739245359361486
iex> Geocalc.bearing(paris, berlin)
1.0178267866082613
iex> berlin = %{lat: 52.5075419, lon: 13.4251364}
iex> paris = %{latitude: 48.8588589, longitude: 2.3475569}
iex> Geocalc.bearing(berlin, paris)
-1.9739245359361486@spec bounding_box(Geocalc.Point.t(), number()) :: list()
Calculates a bounding box around a point with a radius in meters.
Returns an array with 2 points (list format). The bottom left (southwest) point, and the top-right (northeast) one.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> radius = 10_000
iex> Geocalc.bounding_box(berlin, radius)
[[52.417520954378574, 13.277235453275123], [52.59756284562143, 13.573037346724874]]Calculates a bounding box for a list of points.
Returns an array with 2 points (list format). The bottom left (southwest) point, and the top-right (northeast) one.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> london = [51.5286416, -0.1015987]
iex> paris = [48.8588589, 2.3475569]
iex> Geocalc.bounding_box_for_points([berlin, london, paris])
[[48.8588589, -0.1015987], [52.5075419, 13.4251364]]@spec contains_point?(list(), Geocalc.Point.t()) :: boolean()
Returns true if the bounding box contains the given point.
examples
Examples
iex> germany = [[47.27, 5.87], [55.1, 15.04]]
iex> berlin = [52.5075419, 13.4251364]
iex> Geocalc.contains_point?(germany, berlin)
true@spec cross_track_distance_to(Geocalc.Point.t(), Geocalc.Point.t(), Geocalc.Point.t()) :: number()
Compute distance from the point to great circle defined by start-point and end-point.
Returns distance in meters.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> london = [51.5286416, -0.1015987]
iex> paris = [48.8588589, 2.3475569]
iex> Geocalc.cross_track_distance_to(berlin, london, paris)
-877680.2992295175@spec crossing_parallels(Geocalc.Point.t(), Geocalc.Point.t(), number()) :: tuple()
Calculates the pair of meridians at which a great circle defined by two points crosses the given latitude.
Returns longitudes.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> paris = [48.8588589, 2.3475569]
iex> Geocalc.crossing_parallels(berlin, paris, 12.3456)
{:ok, 123.179463369946, -39.81144878508576}
iex> point_1 = %{lat: 0, lng: 0}
iex> point_2 = %{lat: -180, lng: -90}
iex> latitude = 45.0
iex> Geocalc.crossing_parallels(point_1, point_2, latitude)
{:error, "Not found"}Converts degrees to radians.
Returns radians.
examples
Examples
iex> Geocalc.degrees_to_radians(143.67156782221554)
2.5075419
iex> Geocalc.degrees_to_radians(-10.735322818996854)
-0.18736672945597435@spec destination_point(Geocalc.Point.t(), point_or_bearing(), number()) :: tuple()
Finds point between start and end points in direction to end point with given distance (in meters).
Finds point from start point with given distance (in meters) and bearing. Returns array with latitude and longitude.
examples
Examples
Find destination point by bearing:
iex> berlin = [52.5075419, 13.4251364]
iex> paris = [48.8588589, 2.3475569]
iex> bearing = Geocalc.bearing(berlin, paris)
iex> distance = 400_000
iex> Geocalc.destination_point(berlin, bearing, distance)
{:ok, [50.97658022467569, 8.165929595956982]}
iex> zero_point = {0.0, 0.0}
iex> equator_degrees = 90.0
iex> equator_bearing = Geocalc.degrees_to_radians(equator_degrees)
iex> distance = 1_000_000
iex> Geocalc.destination_point(zero_point, equator_bearing, distance)
{:ok, [5.484172965344896e-16, 8.993216059187306]}
iex> berlin = %{lat: 52.5075419, lon: 13.4251364}
iex> bearing = -1.9739245359361486
iex> distance = 100_000
iex> Geocalc.destination_point(berlin, bearing, distance)
{:ok, [52.147030316318904, 12.076990111001148]}Find destination point by point:
iex> berlin = [52.5075419, 13.4251364]
iex> paris = [48.8588589, 2.3475569]
iex> distance = 250_000
iex> Geocalc.destination_point(berlin, paris, distance)
{:ok, [51.578054644172525, 10.096282782248409]}@spec distance_between(Geocalc.Point.t(), Geocalc.Point.t()) :: number()
Calculates distance between 2 points.
Returns distance in meters.
examples
Examples
iex> berlin = [Decimal.new("52.5075419"), Decimal.new("13.4251364")]
iex> paris = [48.8588589, 2.3475569]
iex> Geocalc.distance_between(berlin, paris)
878327.4291149472
iex> Geocalc.distance_between(paris, berlin)
878327.4291149472
iex> berlin = %{lat: 52.5075419, lon: 13.4251364}
iex> london = %{lat: Decimal.new("51.5286416"), lng: Decimal.new("-0.1015987")}
iex> paris = %{latitude: 48.8588589, longitude: 2.3475569}
iex> Geocalc.distance_between(berlin, paris)
878327.4291149472
iex> Geocalc.distance_between(paris, london)
344229.88946533133Extend the bounds to contain the given bounds.
Returns an array with 2 points (list format). The bottom left (southwest) point, and the top-right (northeast) one.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> london = [51.5286416, -0.1015987]
iex> Geocalc.extend_bounding_box([berlin, berlin], [london, london])
[[51.5286416, -0.1015987], [52.5075419, 13.4251364]]@spec geographic_center(list()) :: Geocalc.Point.t()
Compute the geographic center (aka geographic midpoint, center of gravity) for an array of geocoded objects and/or [lat,lon] arrays (can be mixed).
Any objects missing coordinates are ignored. Follows the procedure documented at http://www.geomidpoint.com/calculation.html.
examples
Examples
iex> point_1 = [0, 0]
iex> point_2 = [0, 3]
iex> Geocalc.geographic_center([point_1, point_2])
[0.0, 1.5]@spec in_area?( Geocalc.Shape.Circle.t() | Geocalc.Shape.Rectangle.t() | Geocalc.Shape.Ellipse.t(), Geocalc.Point.t() ) :: boolean()
Check if a point is inside area.
Returns true if inside area, false if not.
examples
Examples
iex> area = %Geocalc.Shape.Circle{latitude: 48.856614, longitude: 2.3522219, radius: 1000}
iex> point = %{lat: 48.856612, lng: 2.3522217}
iex> Geocalc.in_area?(area, point)
true@spec intersection_point( Geocalc.Point.t(), point_or_bearing(), Geocalc.Point.t(), point_or_bearing() ) :: tuple()
Finds intersection point from start points with given bearings.
Returns array with latitude and longitude. Raise an exception if no intersection point found.
examples
Examples
Find intersection point by bearing:
iex> berlin = [52.5075419, 13.4251364]
iex> berlin_bearing = -2.102
iex> london = [51.5286416, -0.1015987]
iex> london_bearing = 1.502
iex> Geocalc.intersection_point(berlin, berlin_bearing, london, london_bearing)
{:ok, [51.49271112601574, 10.735322818996854]}
iex> berlin = %{lat: 52.5075419, lng: 13.4251364}
iex> bearing = Geocalc.degrees_to_radians(90.0)
iex> Geocalc.intersection_point(berlin, bearing, berlin, bearing)
{:ok, [52.5075419, 13.4251364]}Find intersection point by point:
iex> berlin = {52.5075419, 13.4251364}
iex> london = {51.5286416, -0.1015987}
iex> paris = {48.8588589, 2.3475569}
iex> Geocalc.intersection_point(berlin, london, paris, london)
{:ok, [51.5286416, -0.10159869999998701]}Raise exception when no intersection points:
iex> berlin_1 = %{lat: 52.5075419, lng: 13.4251364}
iex> berlin_2 = %{lat: 52.5075419, lng: 13.57}
iex> bearing = Geocalc.degrees_to_radians(90.0)
iex> Geocalc.intersection_point(berlin_1, bearing, berlin_2, bearing)
{:error, "No intersection point found"}Returns true if the bounding box intersects the given bounds.
Two bounds intersect if they have at least one point in common.
examples
Examples
iex> germany = [[47.27, 5.87], [55.1, 15.04]]
iex> poland = [[49.0, 14.12], [55.03, 24.15]]
iex> Geocalc.intersects_bounding_box?(germany, poland)
true@spec max_latitude(Geocalc.Point.t(), number()) :: number()
Calculates maximum latitude reached when travelling on a great circle on given bearing from the point (Clairaut's formula). Negate the result for the minimum latitude (in the Southern hemisphere).
The maximum latitude is independent of longitude; it will be the same for all points on a given latitude.
Returns radians.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> paris = [48.8588589, 2.3475569]
iex> bearing = Geocalc.bearing(berlin, paris)
iex> Geocalc.max_latitude(berlin, bearing)
55.953467429882835@spec outside_area?( Geocalc.Shape.Circle.t() | Geocalc.Shape.Rectangle.t() | Geocalc.Shape.Ellipse.t(), Geocalc.Point.t() ) :: boolean()
Check if a point is outside area.
Returns true if outside area, false if not
examples
Examples
iex> area = %Geocalc.Shape.Circle{latitude: 48.856614, longitude: 2.3522219, radius: 10}
iex> point = %{lat: 48.856418, lng: 2.365871}
iex> Geocalc.outside_area?(area, point)
trueReturns true if the bounding box overlaps the given bounds.
Two bounds overlap if their intersection is an area.
examples
Examples
iex> germany = [[47.27, 5.87], [55.1, 15.04]]
iex> berlin_suburbs = [[52.338261, 13.08835], [52.67551, 13.76116]]
iex> Geocalc.overlaps_bounding_box?(germany, berlin_suburbs)
trueConverts radians to degrees.
Returns degrees.
examples
Examples
iex> Geocalc.radians_to_degrees(2.5075419)
143.67156782221554
iex> Geocalc.radians_to_degrees(-0.1015987)
-5.821176714015797@spec within?([Geocalc.Point.t()], Geocalc.Point.t()) :: boolean()
Calculates if a point is within a polygon.
Returns boolean.
examples
Examples
iex> point = [14.952242, 60.1696017]
iex> poly = [[24.950899, 60.169158], [24.953492, 60.169158], [24.953510, 60.170104], [24.950958, 60.169990]]
iex> Geocalc.within?(poly, point)
false
iex> point = [24.952242, 60.1696017]
iex> poly = [[24.950899, 60.169158], [24.953492, 60.169158], [24.953510, 60.170104], [24.950958, 60.169990]]
iex> Geocalc.within?(poly, point)
true
iex> point = [24.976567, 60.1612500]
iex> poly = [[24.950899, 60.169158], [24.953492, 60.169158], [24.953510, 60.170104], [24.950958, 60.169990]]
iex> Geocalc.within?(poly, point)
false@spec within?(number(), Geocalc.Point.t(), Geocalc.Point.t()) :: boolean()
Calculates if a point is within radius of the center of a circle.
Returns boolean.
examples
Examples
iex> berlin = [52.5075419, 13.4251364]
iex> paris = [48.8588589, 2.3475569]
iex> Geocalc.within?(10, paris, berlin)
false
iex> Geocalc.within?(10, berlin, paris)
false
iex> san_juan = %{lat: 18.4655, lon: 66.1057}
iex> puerto_rico = %{lat: 18.2208, lng: 66.5901}
iex> Geocalc.within?(170_000, puerto_rico, san_juan)
true