Difference between revisions of "Help:Classification in categories"

Latest revision as of 14:40, 20 April 2012

Over-categorization with double entries should be avoided, as all media appear in both categories.

Classification in general

Classification in categories is essential to find quickly articles or media types or just for a classification. [[Category:Flora]] creates a category. But it has to be mentioned that it will not be found by a standard search, because this page isn't established yet really. To do so you have to click the red link from the category's name and add a description or purpose of this particular category. An added colon, however, creates only a link to the category, e.g.: [[:Category:Flora]]. Hereby a convenient way of adding categories is to activate the “HotCat” categorisation tool in your own preferences in section “Gadgets”.

When creating categories, one should use only usual letters. Other kinds of characters may be uniformative (such as ', ", the x symbol), or be put after z (such as the Polish Ł).

Sorting

In general each category or page is sorted by its name, but it's also possible to alter this behaviour:

Now this category will be sorted differently as given and not like “Abies alba”. In a similar way you can alter the way of sorting of categorised words themselves:

Example  

On a page named “Resource Subtype” you can sort it to “Subtype” (i.e. letter S) by adding the optional sorting word after the vertical bar “|”: [[Category:Metadata | Subtype]].

Taxonomic sorting

A quick glance at the page [[1]] shows a very long list of red categories with only one member. It seems that Metadata creates automatically categories, even if users are not aware. Categories could become a potent way to retrieve images. In particular, when the main keyword is a scientific name, we could create a category Species name, included in a category Genus name, and then Family name... One thing we have to do is to agree on a classification system. For higher plants, I will use APG III.

In order to be useful, such a system should be as flat as possible. For example, infraspecific taxa could be simply merged into the species. Intermediate taxa should be avoided (such as Triticeae between Triticum and Poaceae), unless there are too many names. Above family names, I suggest (for plants) to limit to such large "taxa" as "flowering plants" or "ferns", and then to "Plants".

In order to do that, when uploading an image, you simply have to check that the species name is specified as a category. If you have time, you can then go to the category Species name, and add the link to the category Genus name, and so on... But other people can also do it, and it has to be done only once.Michel Chauvet

Automatic sorting

If you want a page name like “Bombus hortorum” sorted automatically by “hortorum, Bombus” then use template: PAGENAME word2-n, word1. Just insert on the category page:

{{DEFAULTSORT: {{PAGENAME word2-n, word1}}}}

Nesting

It's also possible to nest categories in the following way and create sub-categories:

Images in subcategories

As images are shown by default just from the current category level it might be comfortable to browse also the images form subcategory levels. To do so, use

{{Images in Subcategories}}

… and by default up to 10 images are shown also from subcategories.

Check out

To check unused categories the following links might be very helpful:

• categories
• uncategorized files
• uncategorized categories
• uncategorized templates

Some technical problems

Note that if you want to add relevant categories to an image used from Commons, it is advised to wait 2 minutes before doing this, else the automatic downloading of the original description will fail because your manual description will take precedence.

Classification using template “Metadata”

For media data a special template was developed that handles categorisation as well. Usually you can use the “Edit with form”-link next to “Edit” for changing data of a file. Here is an example for a German description of a Heteropteran wing description:

{{Metadata
| Type=StillImage
| Title=Wanzenflügel mit Legende
| Caption = Ein Wanzenflügel für Erklärungen in Bestimmungsschlüsseln.
| Scientific Names = Heteroptera
| Common Names = Wanzen; Ploštice; Heteropter; Luteet
| Metadata Language=de
| Language = de
| Creators= [[User:GiselaWeber]]
| Subject Category = Heteroptera
| General Keywords = Morphological details; Legends; Schematic drawings; Wings (Insecta)
}}

…which produces:

Wanzenflügel mit Legende
Caption: Ein Wanzenflügel für Erklärungen in Bestimmungsschlüsseln.
Creators: User:GiselaWeber Copyright Statement: Copyrighted Material; the copyright remains with the author (not this web publication) License Statement: Creative Commons: Author Attribution Required, Share-Alike (cc-by-sa 3.0) World Region: (Desirable information missing!) Country Codes: (Desirable information missing!) Subject Category: Heteroptera General Keywords: Morphological details; Legends; Schematic drawings; Wings (Insecta) Scientific Names: Heteroptera Common Names: Wanzen; Ploštice; Heteropter; Luteet	Type: StillImage Language: Deutsch

“Subject Category” and “General Keywords” are hereby automatically categorised. And of course you can provide less or more information, but the much information you can give the better it is. For details and parameters of this template see on documentation’s page.

Copy and paste: text snippets

Some useful text snippets for copy and paste for …
sorting a category according to e.g. “hortorum, Bombus”

{{Taxinfo}}
{{DEFAULTSORT: {{PAGENAME word2-n, word1}}}}
[[Category: ]]

additional images from subcategories

{{Taxinfo}}
{{Images in Subcategories}}
[[Category: ]]