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manual:chapter3:units [2019/11/19 13:34]
claudio [Custom Units]
manual:chapter3:units [2019/11/19 13:34] (current)
claudio [Custom Units]
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 Custom units can also be defined as derived units, in terms of other base units. This is done with the ''​UDEFINE''​ command. For example typing ''​750_ml''​ ''​%%'​mug'​%%''​ ''​UDEFINE''​ would define a unit named ''​mug''​ as 750 ml. From that moment ''​mug''​ can be used in the exact same way as any system-defined unit, and it will be considered consistent with all other volume units. Custom units can also be defined as derived units, in terms of other base units. This is done with the ''​UDEFINE''​ command. For example typing ''​750_ml''​ ''​%%'​mug'​%%''​ ''​UDEFINE''​ would define a unit named ''​mug''​ as 750 ml. From that moment ''​mug''​ can be used in the exact same way as any system-defined unit, and it will be considered consistent with all other volume units.
  
-Custom units may also accept SI prefixes, but this needs to be explicitly enabled during the unit definition. To create a custom unit that accepts SI prefixes, the name of the unit needs to be preceded by a question mark ''?''​ when the unit is defined. For example, following the previous example, ​in order for the unit ''​mug''​ to accept SI prefixes, the definition should be done typing ''​750_ml''​ ''​%%'?​mug'​%%''​ ''​UDEFINE''​ creates a unit ''​mug''​ exactly as before, except now ''​1_[Mmug]''​ ''​UBASE''​ will produce ''​750_m^3'',​ as expected.+Custom units may also accept SI prefixes, but this needs to be explicitly enabled during the unit definition. To create a custom unit that accepts SI prefixes, the name of the unit needs to be preceded by a question mark ''?''​ when the unit is defined. For example, following the previous example, for the unit ''​mug''​ to accept SI prefixes, the definition should be done typing ''​750_ml''​ ''​%%'?​mug'​%%''​ ''​UDEFINE''​ creates a unit ''​mug''​ exactly as before, except now ''​1_[Mmug]''​ ''​UBASE''​ will produce ''​750_m^3'',​ as expected.
  
 New units can also be defined in terms of new (unknown) base units. For example typing ''​3_apples''​ ''​%%'​oranges'​%%''​ ''​UDEFINE''​ will define ''​oranges''​ as equivalent to 3 ''​apples'',​ where ''​apples''​ is a base unit (amount of fruit?) that may or may not have been explicitly defined before. New units can also be defined in terms of new (unknown) base units. For example typing ''​3_apples''​ ''​%%'​oranges'​%%''​ ''​UDEFINE''​ will define ''​oranges''​ as equivalent to 3 ''​apples'',​ where ''​apples''​ is a base unit (amount of fruit?) that may or may not have been explicitly defined before.
  • manual/chapter3/units.txt
  • Last modified: 2019/11/19 13:34
  • by claudio