Latlong

Provides a parser for latitude and longitude strings. Handles various formats for specifying a position. Parsing returns a tuple latitude and longitude in a signed decimal degree format. The parser accepts the following formats:

• 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
• 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)

Example Usage

iex> LatLong.parse "39.1371°N, 88.65°W"
{39.1371, -88.65}

iex> LatLong.parse "39.1371°E", "88.65°W"
{:error, "Error Parsing Latitude"}

The second example above returns an error since latitude is NS and E was specified. The correct function call is:

iex> LatLong.parse "39.1371°N", "88.65°W"
{39.1371, -88.65}

Road Map

A formatting function needs to be provided that takes a format string such as these:

d.°D         39.1371°N
d° m' s"D     39° 20' 33"S
Sd.           39.1371
Sd m.'         39 20.5

Formatting could also be provided with parsing for a 'strict' mode. After parsing, a format string could be returned that defines the format encountered during the parse. This could be useful for reformatting in the format provided for parsing.

A mode could be added that insures both the longitude and the latitude use the same format.

Installation

If available in Hex, the package can be installed as:

1. Add latlong to your list of dependencies in mix.exs:

```elixir
def deps do
  [{:latlong, "~> 0.1.0"}]
end
```