Units[Converter]

 add a unit to or modify a unit in the Unit Converter

Parameters

 unit - symbol; unit name opts - equation(s) of the form option=value where option is one of 'display', 'default', or 'make'; specify options for the unit

Description

 • The AddUnit(unit, opts) function adds a new unit to or modifies options of an existing unit in the Unit Converter.
 • If the dimension corresponding to unit is not in the Unit Converter, the command Units[Converter][AddDimension](convert(unit, 'dimensions', 'base')) is executed automatically.
 • This procedure accepts symbols and variations in spelling. For example, $\frac{m}{s}$, meters/second, and metre/second represent the same unit in the Unit Converter.
 • You describe the options of the unit by using the optional arguments. The opts argument can contain one or more of the following equations.
 'display'=string
 This option gives the text that appears in the drop-down boxes in the Unit Converter dialog box.  If this option is not given, the entry is unit.
 'default'=From, To, or a set of these
 This option specifies whether the unit appears as the default unit in the From: or To: drop-down box when the corresponding dimension is selected in the Unit Converter dialog box.
 'make'=truefalse
 This option specifies whether the conversion tables are rebuilt after the unit has been added to the Unit Converter.  By default, this option is set to true. If $10$ or more dimensions or units are being added to or removed from the Unit Converter in the same execution group, it is recommended that you execute the Units[Converter][MakeConverter]() calling sequence afterward.

Examples

 > $\mathrm{with}\left(\mathrm{Units}\left[\mathrm{Converter}\right]\right):$
 > $\mathrm{AddUnit}\left(\frac{'\mathrm{parsec}'}{'\mathrm{year}\left[\mathrm{Julian}\right]'},'\mathrm{display}'="parsecs per Julian year"\right)$

Change the spelling in the text of 'centimeters per second'

 > $\mathrm{AddUnit}\left(\frac{'\mathrm{cm}'}{'s'},'\mathrm{display}'="centimetres per second"\right)$

Set the already existing unit of kilowatt hour as the default 'From' unit

 > $\mathrm{AddUnit}\left('\mathrm{kW}''h','\mathrm{default}'='\mathrm{From}'\right)$