latlong

v0.1.0

latlong v0.1.0 LatLong

A parser for all the ways that a longitude or latitude may be specified. Comments and suggestions on how this might have been better written are welcome. The following lat long formats are allowed … all are equivalent:

  • 38.8977, -77.0365
  • 38° 53’ 51.635” N, 77° 2’ 11.507” W
  • 38 53 51.635 N, 77 2 11.507 W
  • N 38° 53’ 51.635”, W 77° 2’ 11.507”
  • N 38 53 51.635, W 77 2 11.507
  • 38 53 51.635, -77 2 11.507

And some other examples that are for different locations:

  • -31.96, 115.84
  • 90, 0 (North Pole)
  • 41 25 01N, 120 58 57W
  • 41°25’01”N, 120°58’57”W
  • S17 33 08.352, W69 01 29.74
  • 41 25N, 120 58W
  • 41°25’N, 120°58’W
  • N41 25.117, W120 58.292
  • 41 N, 120 W
  • 41°N, 120°W
  • N41.092, W120.8362
  • 90S, 0E (South Pole)

In addition, the latitude may be in one format and the longitude in another.

Parsing

The strings are parsed with a state machine checking the next part of the string, saving the various parts in a map. Each pass of the state machine provides the next Float if available and the next grapheme. The state machine lets the call fall to the appropriate state handler and then the next part is examined until there isn’t anything left in the string.

Summary

Types

latitude()
longitude()
message()

Functions

parse(latlong)

Parses string representations of a latitude and longitude into decimals. The latitude and longitude must be provided as single string argument with a separating comma

parse(latitude, longitude)

Parses string representations of a latitude and longitude into decimals. The latitude and longitude must be provided as string arguments

Types

latitude() 
latitude() :: number
longitude() 
longitude() :: number
message() 
message() :: String.t

Functions

parse(latlong) 
parse(String.t) :: {latitude, longitude} | {:error, message}

Parses string representations of a latitude and longitude into decimals. The latitude and longitude must be provided as single string argument with a separating comma.

parse(latitude, longitude) 
parse(String.t, String.t) ::
  {latitude, longitude} |
  {:error, message}

Parses string representations of a latitude and longitude into decimals. The latitude and longitude must be provided as string arguments.