GIS.Math.Spherical

Utilities to compute area, perimeterPolygon, etc. on the surface of a sphere.

Documentation

areaPolygon :: Polygon -> Double

Uses areal projection; then finds area of the polygon. Result is in km^2

perimeterPolygon :: Polygon -> Double

relativeCompactness :: Polygon -> Double

Relative compactness. Dimensionless.

totalPerimeter :: [Polygon] -> Double

Given a list of polygons, return the total perimeter.

Spherical geometry

areaTriangle :: Point -> Point -> Point -> Double

Compute the area of a triangle using LHuilliers formula

areaConvex :: Polygon -> Double

Compute the area of a convex polygon on the surface of a sphere.

Internal functions

distance :: (Double, Double) -> (Double, Double) -> Double

Distance in kilometers between two points given in degrees.