Template:Track gauge/doc

This template accepts a track gauge and returns that defined track gauge well formatted, plus the converted size value by another unit:
 * &rarr;
 * &rarr;

Extra options are available:
 * &rarr;
 * &rarr;
 * &rarr;

Input options
The first parameter specifies the gauge: Rail track gauges can be entered as they are defined: in units mm or ft in. Also common accepted names can be used, see below.

The input value (a length, in metric or imperial units) must be a defined track gauge. Currently 135 gauges are defined by metric units, and 148 by imperial units. Some are defined in both unit systems, such as the standard gauge.


 * When an input value is not recognised by the template, the template simply returns the input as it is: &rarr;
 * The page with this unknown input is also listed in a maintenance category, in the background, that signals interested editors that there is a new rail gauge used in Wikipedia. More on this below.


 * Some gauges in metric are defined in metres: 1 m is recognised. However, it is not available for all metric defined gauges. Using mm is a safer bet.

Formatting input
When entering a track gauge (like, these are formatting options. Keep in mind that only defined gauges are recognised.

Spacing is free, and fractions can be used in imperial units. Primes ( and  ) may be used for [foot, inch]. Any [foot, inch] size can be entered in all-inches ( equals  and  ).

Parameters

 * Names can be universal, being defined worldwide. For example: Iberian gauge, . Other names can be localor culturally restricted, for example the name "Cape gauge" is used in South Africa for, but not in Japan (in Japan that same track gauge is not named).
 * Also, two sizes can lead to one gauge name.

Named gauges
Established gauge names can be entered. The word "gauge" can be omitted. Case-insensitive (A=a). See also the al, allk parameters (below), to show a gauge name in the outcome.

English variant (ENGVAR)
This template defaults to UK-English. For articles written in US-English, set parameter engvar to en-US. In this situation, the US-English spelling is shown:
 * &rarr;

As of 2016, the only two gauges impacted are the 1000 mm and 1009 mm gauges. In UK-English these are spelled metre, in US-English these are spelled meter.

Why not use ?
To convert a track gauge, using Convert comes to mind. For example, standard gauge:
 * {{Convert|1435|mm|ftin|abbr=on} } &rarr; 1435 mm


 * However, this has some disadvantages. First of all, track gauges are defined by an institute, not just measured. The list of those defined track gauges is limited, and overseeable (today some 270 physical sizes are defined).


 * Using allows us to track (follow) all articles with a specific gauge. This way the list can be made more accurate, correct and complete.


 * Also, the track definition can be directly linked to the sourcing article:.


 * Further more, the template allows to recognise named gauges such as "Russian gauge".

Tracking category

 * detects that an undefined gauge is entered, and signal the page for maintenance. For example, metre gauge is only defined in metric. Entering an imperial size would categorise that article in.

TemplateData
{	"description": "The template formats a track gauge size into standard notation and adds the conversion into the imperial/metric (other) size", "params": { "1": {			"label": "Track gauge definition", "description": "Defined track gauge, in mm or ft in. Also can accept: ' '', m, gauge name", "type": "string", "required": true },		"lk": { "label": "Link top measurement units", "description": "=on: adds link to the gauge defining article", "type": "string" },		"al": { "label": "Alternative name", "description": "=on: Add gauge name (if existing)", "type": "string" },		"allk": { "label": "Alternative name, linked", "description": "=on: Add gauge name (if existing) and link to its wiki page", "type": "string" },		"disp": { "label": "Display converted gauge", "description": "Separator for the converted value: 1=none (first value only); =s, /: slash separator; =Any text (2 or more characters): Any literal text written between the two values.", "type": "string", "default": "(...) brackets" },		"first": { "label": "Which unit to mention first", "description": "=met: metric first; =imp: imperial first (default: input unit)", "type": "string", "default": "By input" },		"nowrap": { "label": "Allow line wrapping of text", "description": "wrap=off, on, all: allows lin breaking between the two measurements. Default: on. 'all' disallows linebreaking wiothing an alternative name", "type": "string", "default": "off" },		"unitlink": { "label": "Wikilink units", "description": "=on: do wikilink", "type": "string" },		"addcat": { "label": "Categorize page", "description": "=no: do not categorize", "type": "string", "default": "yes" },		"engvar": { "label": "ENGVAR", "description": "When set to en-US, \"metRE\" is spelled \"metER\"", "example": "meter gauge only", "default": "en-UK" },		"comma": {} },	"paramOrder": [ "1",		"lk", "al", "allk", "disp", "first", "nowrap", "unitlink", "addcat", "engvar", "comma" ] }

External links; sources
Sources
 * Light Rail Transit Association (LRTA)
 * Latin America is very well covered
 * UK based, covering most countries


 * de:Liste_der_Spurweiten (checking here in Template talk:Track gauge/dewiki list)

Scaled rail models


 * DGEG (German) Spurweiten_Auswahl 107-Spurweiten_Auswahl Spurweiten_Auswahl