GeoPath
GeoPath[{loc1,loc2},pathtype]
is a GeoGraphics primitive that represents a path of type pathtype between locations loc1 and loc2.
GeoPath[{loc1,loc2,…},pathtype]
represents a path formed by joining paths of type pathtype between consecutive locations loci.
GeoPath[{loc1,d,α},pathtype]
represents a path moving from location loc1 a distance d with initial bearing α.
GeoPath[{{loc11,loc12,…},{loc21,…},…},pathtype]
represents a disjoint collection of paths of type pathtype.
Details and Options
- The locations loci can be specified as latitude and longitude coordinates {lat,lon} in degrees, as GeoPosition[{lat,lon}], or as named entities Entity[…].
- Entities will be interpreted as the position determined by their "Position" property.
- GeoPath supports the geographic path types:
-
"Geodesic" geodesic path between points "Rhumb","RhumbLine","Loxodrome" path of constant bearing between points "GreatEllipse","GreatCircle" path on a plane through Earth's center - GeoPath[{loc1,…}] represents a path of type "Geodesic".
- For multiple locations loci in a "Geodesic" path, each pair of consecutive locations is joined by a geodesic, but the complete path will not be a geodesic in general. The same can be said of other path types.
- A combination of multiple steps of distances di with respective initial bearings αi can be represented using GeoPath[{loc1,GeoDisplacement[{d1,α1}],GeoDisplacement[{d2,α2}],…},pathtype].
- Long paths will generically not appear straight in the map.
- Special named geo paths include:
-
GeoPath[{"Parallel",lat}] parallel of latitude lat, extending 360° in longitude GeoPath[{"Meridian",lon}] meridian of longitude lon, extending 180° in latitude GeoPath[{"Parallel",lat,{lon1,lon2}}] parallel of latitude lat, from longitude lon1 to lon2 GeoPath[{"Meridian",lon,{lat1,lat2}}] meridian of longitude lon, from latitude lat1 to lat2 GeoPath["Equator"] parallel of latitude 0° GeoPath["NorthernTropic"] parallel of latitude 23.43703° GeoPath["SouthernTropic"] parallel of latitude -23.43703° GeoPath["ArcticCircle"] parallel of latitude 66.56297° GeoPath["AntarcticCircle"] parallel of latitude -66.56297° GeoPath["GreenwichMeridian"] meridian of longitude 0° GeoPath["DateLineMeridian"] meridian of longitude 180° GeoPath["DateLine"] international date line - Line thickness can be specified using Thickness or AbsoluteThickness, as well as Thick and Thin.
- Line dashing can be specified using Dashing or AbsoluteDashing, as well as Dashed, Dotted, etc.
- Line shading or coloring can be specified using CMYKColor, GrayLevel, Hue, Opacity, or RGBColor.
- The option VertexColors->{c1,c2,…} can be used to specify that the color of the line should interpolate between colors ci specified for each point.
- Joining of line segments can be specified using JoinForm.
- Line caps can be specified using CapForm.
Examples
open allclose allBasic Examples (5)
Scope (8)
Options (3)
Applications (4)
A geo triangle, with geodesic sides, in the "LambertAzimuthal" projection:
The same geo triangle in the "Equirectangular" projection:
Several paths with the same displacement data but with different initial positions. Use Arrow:
Create tooltips to allow coordinates to be read off geo grid lines drawn as geo paths:
Properties & Relations (7)
A line of constant rhumb (constant angle with respect to all meridians) eventually spirals around a pole:
Neither the rhumb line (red) nor the geodesic (green) is a straight line (given for comparison in black), using the default equirectangular geo projection:
The rhumb line is straight in the Mercator projection, and now it is superimposed on the black line:
The geodesic is straight in an azimuthal projection centered at one of the points, and now it is superimposed on the black line:
Get the latitude and longitude of the vertices on a sphere:
Draw the geodesics among those vertices on a world map:
A geo disk or a geo circle is constructed using the endpoints of geodesics starting from its center:
The endpoint of a geodesic path may be computed using GeoDestination:
Check the displacement data of the path using GeoDistance and GeoDirection:
Or directly with GeoDisplacement:
Construct a geodesic path that leaves London with NE direction and goes around the Earth three times:
Computations are performed on an ellipsoidal Earth by default. Hence geodesic paths do not close:
Use a spherical model for the Earth. Then the geodesic is closed:
Or use a great ellipse, which is always closed:
For the low eccentricity of the Earth, geodesics are close to great ellipses:
Interactive Examples (1)
Neat Examples (3)
Show an effect of the Earth's curvature using four path segments:
Draw the four geodesic segments:
Now follow four loxodrome segments instead:
Move from the Temple of Zeus along a path given by the first 3141 terms of the continued fraction of :
The path ends just a few miles east of Kossuth, Mississippi:
Study a candidate hexagonal tiling on the Earth. Recursively move from Denver in steps of 100 miles:
For each geodesic of initial bearing , draw two new ones with bearings and :
The resulting set of geodesics does not overlap, due to the curvature of the Earth's surface:
Text
Wolfram Research (2014), GeoPath, Wolfram Language function, https://reference.wolfram.com/language/ref/GeoPath.html.
CMS
Wolfram Language. 2014. "GeoPath." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/GeoPath.html.
APA
Wolfram Language. (2014). GeoPath. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/GeoPath.html