-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | For manipulating GPS coordinates and trails.
--   
--   Useful for manipulating GPS coordinages (in various forms), building
--   paths, and performing basic computations
@package gps
@version 0.6


-- | A basic GPS library with calculations for distance and speed along
--   with helper functions for filtering/smoothing trails. All distances
--   are in meters and time is in seconds. Speed is thus meters/second
module Data.GPS

-- | Distances are expressed in meters
type Distance = Double

-- | Angles are expressed in radians from North. 0 == North pi/2 == West pi
--   == South (3<i>2)pi == East == - (pi </i> 2)
type Heading = Double

-- | Speed is hard coded as meters per second
type Speed = Double
type Vector = (Distance, Heading)
type Trail a = [a]

-- | North is 0 radians
north :: Heading

-- | South, being 180 degrees from North, is pi.
south :: Heading

-- | East is 270 degrees from North
east :: Heading

-- | West is 90 degrees (pi/2)
west :: Heading

-- | radius of the earth in meters
radiusOfEarth :: Double

-- | Direction two points aim toward (0 = North, pi<i>2 = West, pi = South,
--   3pi</i>2 = East)
heading :: (Lat a, Lon a) => a -> a -> Heading
distance :: (Lat a, Lon a) => a -> a -> Distance

-- | Speed in meters per second, only if a <a>Time</a> was recorded for
--   each waypoint.
speed :: (Lat loc, Lon loc, Time loc) => loc -> loc -> Maybe Speed

-- | Given a vector and coordinate, computes a new coordinate. Within some
--   epsilon it should hold that if
--   
--   <pre>
--   dest = addVector (dist,heading) start
--   </pre>
--   
--   then
--   
--   <pre>
--   heading == dmsHeading start dest
--   </pre>
--   
--   <pre>
--   dist    == distance start dest
--   </pre>
addVector :: (Lat c, Lon c) => Vector -> c -> c

-- | Provides a lat/lon pair of doubles in radians
getRadianPair :: (Lat p, Lon p) => p -> (LatitudeType, LongitudeType)
getDMSPair :: (Lat c, Lon c) => c -> (LatitudeType, LongitudeType)

-- | <tt>divideArea vDist hDist nw se</tt> divides an area into a grid of
--   equally spaced coordinates within the box drawn by the northwest point
--   (nw) and southeast point (se). Because this uses floating point there
--   might be a different number of points in some rows (the last might be
--   too far east based on a heading from the se point).
divideArea :: (Lat c, Lon c) => Distance -> Distance -> c -> c -> [[c]]

-- | Find the total distance traveled
totalDistance :: (Lat a, Lon a) => [a] -> Distance

-- | Creates a list of trails all of which are within the given distance of
--   each other spanning atleast the given amount of time.
--   
--   For example <tt>restLocations 50 600</tt> would return lists of all
--   points that are within 50 meters of each other and span at least 10
--   minutes (600 seconds).
--   
--   Note this gives points within fifty meters of the earliest point -
--   wandering in a rest area with a 50 meter radius could result in
--   several rest points ([a,b..]) or even none if the distance between
--   individual points exceeds 50m.
restLocations :: (Lat a, Lon a, Time a) => Distance -> NominalDiffTime -> Trail a -> [Trail a]

-- | Returns the closest distance between two trails (or Nothing if a trail
--   is empty) O( (n * m) * log (n * m) )
closestDistance :: (Lat a, Lon a) => Trail a -> Trail a -> Maybe Distance

-- | Filter out all points that result in a speed greater than a given
--   value (the second point is dropped)
filterByMaxSpeed :: (Lat loc, Lon loc, Time loc) => Speed -> Trail loc -> Trail loc

-- | Uses Grahams scan to compute the convex hull of the given points. This
--   operation requires sorting of the points, so don't try it unless you
--   have notably more memory than the list of points will consume.
convexHull :: (Eq c, Lat c, Lon c) => [c] -> [c]

-- | Reads a GPX file (using the GPX library) by simply concatenating all
--   the tracks, segments, and points (<a>trkpts</a>, <a>trksegs</a>,
--   <a>trks</a>) into a single <a>Trail</a>.
readGPX :: FilePath -> IO (Trail WptType)
instance Eq Turn
instance Ord Turn
instance Show Turn
instance Read Turn
instance Enum Turn