Module format 

Label formatting functions for scale breaks. Analogous to R’s scales package (comma, percent, dollar, scientific, number, SI, ordinal, bytes).

Functions

label_bytes

Byte-size formatter. binary = true uses 1024-based KiB/MiB; otherwise 1000-based kB/MB.

label_comma

Format with comma separators for thousands (e.g., 1,234,567).

label_comma_locale

label_comma with the marks of locale (de-DE: 1.234.567).

label_comma_marks

label_comma with explicit marks: label_comma_marks(",", ".")(1234567.5) is "1.234.567,5".

label_currency

Sign-aware currency formatter (R’s scales::label_currency): the minus sign goes before the prefix (“-€5”, not “€-5”), thousands are grouped with big_mark (e.g. ",", ".", " ", "'"; "" disables grouping), and accuracy rounds to a multiple of it (None = up to two decimals, trailing zeros trimmed). The decimal mark is always ..

label_currency_locale

Currency in the conventions of locale — its symbol, placement and marks: de-DE "1.234,50 €", en-US "$1,234.50", en-GB "£1,234.50", fr-FR "1 234,50 €". Use Locale::with_currency for another symbol.

label_currency_marks

label_currency with an explicit decimal mark as well.

label_dollar

Format as US dollar with thousands separators (e.g., 1234 → “$1,234”, -500 → “-$500”). Equivalent to label_currency("$", "", ",", None).

label_number

General configurable number formatter (R’s scales::label_number). Multiplies by scale, rounds to accuracy (None = trim), groups thousands with ,, and wraps in prefix/suffix — with the minus sign placed before the prefix (-€5). For a custom thousands mark use label_currency.

label_number_locale

label_number (scale 1) with the marks of locale.

label_number_marks

label_number with an explicit decimal mark and thousands mark ("" disables grouping).

label_ordinal

Ordinal formatter: 1 → “1st”, 2 → “2nd”, 3 → “3rd”, 11 → “11th”.

label_percent

Format as percentage (e.g., 0.5 → “50%”).

label_percent_locale

label_percent in the conventions of locale: de-DE / fr-FR "12,3 %", en-US / en-GB "12.3%". accuracy as in label_percent_marks.

label_percent_marks

label_percent with explicit marks and percent suffix ("%", " %"). accuracy is in percentage points (Some(0.1) → one decimal); None matches label_percent.

label_scientific

Format in scientific notation (e.g., 12345 → “1.23e4”).

label_si

SI-prefixed number formatter: 1_500 → “1.5k”, 2.3e6 → “2.3M”, 5e-4 → “500µ”.

Type Aliases

LabelFormatter

A label formatter — any Fn(f64) -> String. The plain label_* functions coerce into this, and the configurable label_number/label_si/… builders return one directly.