Clojure CLI and library to convert an alpha numeric Ordnance Survey grid reference to easting / northing or easting / northing to a grid reference.
Valid input includes:
ST => [300000.0 100000.0] (The bottom right coordinate of the ST grid square)
NN1665071250 => [216650.0 771250.0] (The Ben Nevis)
SU387148 => [438700.0 114800.0] (The Ordnance Survey offices in Southampton)
SU31NE => [435000.0 115000.0] (The 5 km square of the OS office)
TQ336805 => [533600.0 180500.0] (The Tower of London)
"[300000.0 100000.0]" => ST (The bottom right coordinate of the ST grid square)
"216650.0 771250.0" => NN1665071250 (The Ben Nevis)
"[438700 114800]" => SU387148 (The Ordnance Survey offices in Southampton)
"533600 180500" => TQ3360080500 (The Tower of London)
Run the following to build a standalone executable target/gridref using Leiningen:
$ lein bin
Using the standalone executable:
$ gridref <gridref>
or
$ gridref [--figures=<n>] <coordinate>
For full usage and examples see the file resources/cli-usage.
The gridref.core namespace defines the functions gridref2coord and coord2gridref that support converting between a grid reference and coordinate pair. There are also functions to parse input parse-gridref and parse-coord which can help with cleaning up input.
(use 'gridref.core)
; Parsing input
(gridref.core/parse-gridref "su 387 148")
=> "SU387148"
(gridref.core/parse-coord "216650.0 771250.0")
=> [216650.0 771250.0]
; Conversion
(gridref.core/gridref2coord "SU387148")
=> [438700.0 114800.0]
(gridref.core/coord2gridref [438700.0 114800.0] 6)
=> "SU387148"
gridref is available as a Maven artifact from Clojars. To use gridref as a library in a Clojure project you can add this in your project.clj with leiningen:
[gridref "0.1.5"]- Input and output in WTK or GeoJSON?
- http://en.wikipedia.org/wiki/Ordnance_Survey_National_Grid
- http://www.ordnancesurvey.co.uk/docs/support/national-grid.pdf
Copyright © 2013 Matt Walker (walkermatt@longwayaround.org.uk, @_walkermatt on Twitter)
Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.