Formatting numbers

Formatting of numbers affects the output of the xsl:number instruction, and the fn:format-integer() function.

The fn:format-number() function itself is not directly affected by the choice of language or country. If you want to use conventions appropriate to a particular locale, for example using a comma (",") as a decimal point, or using an apostrophe ("'") as a separator between groups of digits, you can define a custom decimal format to achieve this, but this is entirely under the control of the stylesheet or query author, it is not affected by any language settings.

Similarly, some of the numbering sequences used by xsl:number are directly under programmer control: for example format="α" (Greek letter alpha, U+03B1) requests a numbering sequence using Greek letters α, β, γ, δ, ε, ζ, ... This is available regardless of the chosen locale.

In xsl:number and in fn:format-integer() it is possible to request a specific language using the lang attribute/argument. The default for this may be set using the Saxon configuration property DEFAULT_LANGUAGE; failing this, the default is taken from the operating system settings. This option mainly affects formatting of numbers as words (for example, in English, "one", "two", "three", or "first", "second", "third") as requested using the format token "W", "w", or "Ww". This is referred to as spellout numbering.

In SaxonJ-HE, spellout numbering is supported "out of the box" only for English; if any other language is requested, the output falls back to English. There is an API, Configuration.setLocalizerFactory(), allowing plug-in code to be registered for other languages, and there are some open-source components available (issued with the saxon-resources download) providing plug-ins for some common European languages.
In SaxonJ-PE and -EE, spellout numbering is available via the ICU4J library, which supports a large variety of languages. This does not require any special configuration.
In SaxonCS, spellout numbering is not currently available.

As well as spellout numbering, the choice of language also affects ordinal numbering, for example 10 is output as "10th" in English, "10." in German, "10e" in French, and "10º" in Italian.

For more details on numbering using ICU, see Numbers and dates from ICU.

For more details on writing a plug-in for localizing numbers and dates, see Localizing numbers and dates.