Wikipedia:WikiProject Geographical coordinates
From Wikipedia, the free encyclopedia
Any Wikipedian may participate in this project to better organize information in articles containing geographical coordinates. This page and its subpages contain suggestions; it is hoped that this project will help to focus the efforts of other Wikipedians. If you would like to help, please include yourself as participant, inquire on the talk page and see the to-do list there.
NOTE: This is a concept currently under development, so this is subject to change.
[edit] Title
WikiProject on Geographical coordinates
[edit] Scope
This WikiProject aims primarily to establish a standard for uniform handling of latitude and longitude coordinates as given in various Wikipedia articles, somewhat analogous to how ISBN numbers are handled.
[edit] Parentage
The parent of this WikiProject is WikiProject Maps.
[edit] Descendant WikiProjects
[edit] Similar WikiProjects
Other WikiProjects that make use of geographical coordinates include:
- WikiProject Countries
- WikiProject U.S. counties
- WikiProject U.S. states
- WikiProject Mountains
- WikiProject Protected areas
- WikiProject Glaciers
- WikiProject Microformats: Geo
- Meta:Category:Wikimaps
[edit] Participants
Userbox: {{User WikiProject Geographical_coordinates}}
- Egil
- Chinasaur
- mav - (moral support mostly)
- The Plowboy Lifestyle
- User:Docu
- Scott Davis
- User:Llynix - (See [1])
- RHaworth
- redjar
- JMOliver
- W i k i a c c - (here and there)
- nikai
- Sunny256
- Citylover
- Sporki
- Erebus555◄?
- Stefan Kühn - (produce KML-File for Google-Earth)
- pfctdayelise (translate?) - (using m:Google Maps Extension on a private wiki, and loving it)
- nampelkafe
- Kingutd
- Universimmedia - Proposes this page using Google Maps to provide coordinates in Wikipedia format (also for French Wikipedia).
- The Anome -- automatic insertion of tags into articles using User:The Anomebot2 -- 78,000 articles tagged, as of December 2007, and counting...
- Mohau
- DarTar
- Luchinatwalker - (when I can)
- Simijaca
- Buaidh
- User:AndrewBuck
- GregU - I geocode articles with coords (but very slowly)
- Dschwen - WikiMiniAtlas
- Andy Mabbett - particular interest in deployment of the Geo microformat on Wikipedia; see Project Microformats and {{coord}}.
- Neranei - I'll try to help as best I can; if you notice me misplacing something, please let me know on my talk page. Thanks!
- Para - GeoCommons
- Guiltyspark
- Targeman
- User:RobBrisbane - Occasional contributer
- User:DJBarney24 - Extension of this system to Mars and other planets ?
- User:RayKiddy
- User:jpo
- Presidentman - used this page for help on Harding Memorial coordinates
- Nick4404 23:36, 6 September 2007 (UTC)
- Psychless
- Mailer Diablo
- SpencerT♦C
- User:Huwmanbeing – Editing Indiana community information, including location
- Padraic
- Krym66 - adding geocodes to battlefields mostly - keeping an eye on Front page articles also
- Socrates2008 - Geocoding battlefields, shipwrecks, aircraft incidents and Third World locations
- Circle High - High schools in the United States
- Paulshannon (talk) 16:47, 22 November 2007 (UTC)
- Clem Rutter, Rochester,Kent. - Interested in javascript conversions from OSGB to WGS84.
- User:Hailey C. Shannon
- └Frozen┘┌Flame22┐
- User:Viktor Shchedrin (talk)
- User:cosnahang
- User:blood sliver - I'll try
- Dewster_^*'_ 11:11, 16 February 2008 (UTC)
- Geronimo20
- Jbom07
- *Dan T.* (talk) 20:37, 22 March 2008 (UTC)
- Rayhou (talk) 13:11, 29 March 2008 (UTC) - I add coordinates to articles that I randomly come across. I can also cooperate with you guys, just let me know.
- Rajah
- Suyogaerospace - I will help as I can --Suyogaerospacetalk to me! 11:15, 24 April 2008 (UTC)
- scottucsd - Beijing Locations Contributer
- JeremyMcCracken (talk) (contribs) - Add coordinates where they are missing.
- Berkeley Librarian
- Excirial (Talk,Contribs) 18:29, 4 June 2008 (UTC)
- Andrew Maiman (talk) 16:24, 7 June 2008 (UTC) - I've been adding Geotags as I run into articles without them. Let me know if help is needed with a specific set of articles.
[edit] Goals
- Should provide a uniform markup for all geographic coordinates
- Should provide a user-preferred appearance for all geographic coordinates
- Markup should be easy and natural to use
- Should be able to have a uniform, extensible way of accessing all types of map resources, avoiding having direct external links to maps in articles
- Clicking on a reference navigates directly to a page with external pointers to various resources, with coordinates automatically embedded where possible. The resources can be maps of various kinds, topological charts, satellite photos and others.
- Create a database of points, enabling generation of navigatable maps with a clickable icon appearing for every location for which there is a Wikipedia article. This has been implemented for NASA World Wind, Google Earth (see below) and Google maps (see below).
- Serve as a tool for finding Wikipedia articles describing nearby locations. See also meta:Wikipediatlas.
- Adhere to existing Internet standards for geographic coordinates as far as possible
[edit] Markup
The practical usage of coordinate markup in Wikipedia is described in the style guide for geographical coordinates. For use on maps and other services, parameters may also be required.
A complete entry could for example be: {{coord|51|28|40|N|0|0|6|W|type:landmark_scale:2000_region:GB}}
See also: Obtaining coordinates
[edit] Marking project-related pages on Talk page
The template {{WPcoord}} may be added to relevant Talk pages. This adds the page to several categories and displays as:
[edit] Implementation details
[edit] Geo tag
To define a geographical point, the Mediawiki gis extension is required. For further information, see the Mediawiki documentation.
- NOTE: This extension is available, but is currently not enabled for Wikipedia. The functionality is thus currently only available via the following templates:
- {{coor d|48.7767|N|121.8142|W|}} gives
- {{coor dm|48|46.60|N|121|48.85|W|}} gives
- {{coor at dm|48|46.60|N|121|48.85|W|}} gives and adds the coordinates to the article's top right corner
- {{coor dms|48|46|36|N|121|48|51|W|}} gives
- {{coord|48|46|36|N|121|48|51|W|}} gives (output depends on user preferences)
- On the surface of the Earth, 1 minute of arc of latitude corresponds to approx. 1.0 nautical mile or 1.852 kilometer, whereas, 1 arc second of latitude corresponds to approx. 30.87 meters (101.28 ft). Because of the approximate numerical equivalence of minute of arc and nautical mile measures, many people find minutes, in degree-minute (dm) format easier to comprehend than arc seconds in degree-minute-second (dms) format, e.g., for navigation.
The geo tag specifies the coordinates as degrees/minutes/seconds of latitude and longitude, like this:
- <geo>48 46 36 N 121 48 51 W</geo>.
In the article, the tag will appear as
. Seconds, or minutes and seconds, may be omitted. Optionally, the precision of the smallest unit used may be increased using decimals.[edit] Parameters
Following the geographical coordinate, further parameters can optionally be supplied, separated by underscores. This will help in finding suitable map resources, and will become more important when the Wikimaps become fully functional.
[edit] type:T
Sets the type of this location, which will be used for the reverse mapping of the points. Will also set the default map scale. Types are:
Type | Description | Scale |
---|---|---|
country | (e.g. "type:country") | 1:10,000,000 |
state | Where applicable | 1:3,000,000 |
adm1st | Administrative unit of country, 1st level (province, county) | 1:1,000,000 |
adm2nd | Administrative unit of country, 2nd level | 1:300,000 |
city(pop) | City, town or village with specified population. Commas will be ignored in pop. There should be no blanks. | 1:30,000 ... 1:300,000 |
city | City, town or village, unspecified population. Will be treated as a minor city. | 1:100,000 |
airport | 1:30,000 | |
mountain | peaks, mountain passes | 1:100,000 |
isle | Isles, islands | 1:100,000 |
waterbody | Bays, fjords, lakes, reservoirs, ponds, lagoons, estuaries, inland seas... | 1:100,000 |
landmark | Cultural landmark, building of special interest, tourist attraction and other points of interest. | 1:10,000 |
forest | Forests and woodlands | ? |
river | Rivers and canals | ? |
glacier | Glaciers | ? |
Sample:
- {{coor dm|46|43|N|7|58|E|type:mountain}} gives
[edit] scale:N
Sets the desired map scale as 1:N. This will override the default scale. The scale: prefix can be omitted.
[edit] region:R
Sets the preferred map region of coverage, used in selecting appropriate map resources for the area. The region should be supplied as either a two character ISO 3166-1 alpha-2 country code, or an ISO 3166-2 region code. Examples:
|
|
Sample:
- {{coor d|46.9524|N|7.4396|E|region:CH}} focuses the section for Switzerland at .
- {{coor d|52.5164|N|13.3775|E|region:DE-BB}} focuses the section for Germany at .
[edit] globe:G
Specifies other worlds than Earth. Such as Moon.
[edit] source:S
Specifies, where present, the data source and data format/datum, and optionally the original data, presented in parentheses. This is initially primarily intended for use by geotagging robots, so that data is not blindly repeatedly copied from format to format and Wikipedia to Wikipedia, with progressive loss of precision and attributability.
Examples:
- A lat/long geotag derived from a Ordnance Survey National Grid Reference NM 435 355 found in the English-language Wikipedia would be tagged as "source:enwiki-osgb36(NM435355)"
- A latitude-longitude location sourced from data taken from the German-language Wikipedia would be tagged as "source:dewiki" -- and so on, for other language codes;
- A location sourced from the public domain GeoNet Names Server database would be tagged as "source:GNS". No datum or format information is needed, since by default all Wikipedia coordinates are in latitude/longitude format based on the WGS84 datum. Similarly, U.S. locations sourced from the similar public domain GNIS database would be tagged as "source:GNIS".
[edit] Coordinate templates (currently used instead of geo tag)
As of August 2007, there are several different high-level ways of entering coordinates, with no clear consensus on the best way. The most popular techniques are:
- Template:coor title d, Template:coor title dm, and Template:coor title dms. These may be placed anywhere in the article source text, and do not expand in-line; rather, they cause the coordinates to be displayed at the very top of the page, near the article's title, in a somewhat skin-dependent way. See Krasnoyarsk hydroelectric dam for an example.
- Template:coor d, Template:coor dm, and Template:coor dms. These are intended to be used in-line, along with prose text, e.g. "Mount Everest is at {{coor dms|27|59|16|N|86|56|40|E}}", which displays as "Mount Everest is at "
- Template:coor at d, Template: coor at dm, and Template: coor at dms. These produce an inline link as well as a link at the top of the page, in effect combining the
coor
andcoor title
templates. - Template:coord - Offers the functionality of all of the previous, with choice of input format and user-preference for display format, plus a Geo microformat).
- Infoboxes. Many infobox templates for geographic places have a field for specifying a place's coordinates. Typically, these templates make use of one of the lower-level templates already described, and may therefore also cause display in the title bar. See Template:Infobox Settlement and Template:Infobox Mountain for examples (or for usage examples: Los Angeles and Mount Everest).
This replaced various free formats.
If creating new templates or infoboxes, it is important that they are defined using one of the main templates, such as {{coor d}}, {{Coor title d}}, {{Coor at d}}, {{coord}}, etc.
Unless a template uses the coordinates in another way, the main coordinate templates should be the field value:
- e.g. {{infobox lake}} uses "coords = {{coor at d|45|N|6|E|type:waterbody}}
If specific coordinates are to be entered directly into templates, templates other than {{coor *}} or {{coord}} should use the following variables for coordinates:
|
|
Where the United Kingdom's Ordnance Survey grid references are used as the coordinates, use (or create) a template which uses Template:oscoor.
[edit] The map source page (currently Template:GeoTemplate)
To generate the list of map sources, the Mediawiki gis extension is required. The definition of the map sources page is via Wikipedia:Map sources. For further information, see the Mediawiki documentation.
NOTE: This mechanism is available, but currently not enabled for Wikipedia. The current solution is running on an external server as a proof-of-concept, and is available via the template:coor family. The map source page produced is defined in the editable "Wikipedia:Map_sources" (sample currently at Template:GeoTemplate). In the interim solution, the URL of the actual map sources page request is:
The argument follows the same format as the geo tag.
[edit] How to obtain geographical coordinates
See Obtaining geographic coordinates
See also: Category:Articles needing coordinates, Maybe-Checker
[edit] Geodetic system
All coordinates, except Ordnance Survey coordinates (which use their own datum), should be referenced to WGS84, or an equivalent datum.
[edit] Precision
Regardless of how coordinates are obtained, some thought should be given as to the precision used in a Wikipedia article. Generally, the larger the object being mapped, the less precise the coordinates should be. For example, if just giving the location of a city, precision greater than 100 meters is not needed unless specifying a particular point in the city, for example the central administrative building. Specific buildings or other objects of similar size would justify precisions down to 10 meters or even one meter in some cases. A general rule might be to avoid giving precisions greater than one tenth the size of the object described in the absence of a clear reason to do so. Overly precise coordinates can be misleading, by implying that the geographic area is smaller than it truly is.
In the two most-used coordinate representations, degrees-minutes-seconds and decimal degrees, precision is, as a useful approximation,
|
|
Distances along lines of latitude are the same at the equator but shrink toward the poles. Unless there is specific reason to take this into account, the distances along lines of longitude should suffice as a guide.
You can calculate the number of kilometers per degree of longitude using one of the following approximation formulas (θ is the latitude in degrees):
Best:
Better: (6378 is Earth radius at equator)
Sufficient:
[edit] Tools and applications based on coordinates from Wikipedia
Articles (and coordinates) can be found through the pages using the templates in Category:Coordinates templates
[edit] NASA World Wind Samples
All examples use NASA World Wind, with the Wikipedia overlay. This is purely meant as an example of one thing that a coordinated concept for geographical coordinates can be used for.
[edit] View Wikipedia in Google Earth
Project Wikipedia-World scan 11 Dumps (ca,cs,de,en,eo,es,fi,fr,nl,pt,ru) and provides:
- dynamic Google-Earth layers in 21 languages. For instance: english Layer
- static Google-Earth layers in 10 language with different folders (Castles, Parks,...), Download at webkuehn.de
- SQL-Data off all scanned coordinates
[edit] Visualization of Wikipedia articles with Google Maps
- PINTOMAP searches the whole Wikipedia-Database for coordinates and visualizes them on a Google-Map.
- www.geonames.org over 800,000 Wikipedia articles in 230 languages on Google maps. The placemarks include short descriptions of the displayed items, extracted from the Wikipedia articles. Webservices for full text search and reverse geocoding of wikipedia articles.
[edit] WikiMiniAtlas JavaScript plugin
WikiMiniAtlas is a JavaScript to add to your monobook.js. It adds a draggable and zoomable (just like GoogleMaps) map to all geo-coded articles. Clickable labels with links other geocoded articles are placed on the map to allow spatial browsing of wikipedia. Map layers include satellite images (using Landsat7 data) with zoomlevels down to a resolution <100m, and daily updated MODIS satellite data.
WikiMiniAtlas is currently enabled on Wikipedia (by clicking on the globe () beside the coordinates).
[edit] All geodata in SQL file format
- Project Wikipedia-World, provides the complete database for download in SQL-file format.
[edit] Export multiple coordinates
Kmlexport tool: Pages marked with multiple coordinates or categories of articles with coordinates can be exported as KML (for use in Google Earth, for example). This tool and some alternatives can be found on clicking the coordinates or by applying the {{GeoGroupTemplate}} template on a page.
The Kmlexport can be used directly or through Google Maps; see for example Colmar Pocket or Category:Capitals in Europe. Export from articles is real-time, export from categories is based on stored extractions (may be several weeks old).
KML may be converted in other formats, suitable as Points of Interest (POI) for GPS systems.
Other sources:
[edit] World map displaying the concentration of wikipoints
[edit] See also
- Wikipedia:Manual of Style (dates and numbers)#Geographical coordinates
- Wikipedia:Coordinate-referenced map templates (inactive)
- Wikipedia:WikiProject Maps/Source materials
- Category:Cartography
- meta:Wikipediatlas
- meta:Geographical data
- http://lists.wikimedia.org/pipermail/wikitech-l/2005-March/015851.html
- ISO 6709
- meta:WikiGPS
- meta:WikiProjects Geographical coordinates
- Commons:Commons:Geocoding
[edit] External links
References
- RFC1876 How latitude and longitude are stored in a DNS record.
- RFC2426 Chapter 3.4.2: Text/directory MIME type GEO
- draft-daviel-http-geo-header-04
- draft-daviel-http-geo-tag-06
- draft-royer-timezone-registry-01
Various
Convert between coordinate systems
- http://www.fcc.gov/mb/audio/bickel/DDDMMSS-decimal.html
- http://www.nearby.org.uk/coord.cgi Handles many types of coordinate systems, various postcodes, telephone area codes etc