Quantity

Quantity[magnitude,unit]

represents a quantity with size magnitude and unit specified by unit.

Quantity[unit]

assumes the magnitude of the specified unit to be 1.

Details and Options

  • Quantity has attribute HoldRest and preserves the structure of unit.
  • The specified unit should be a string or operation of strings representing the Quantity expression's unit value.
  • Quantity[unit] will produce a canonicalized Quantity with a magnitude of 1.
  • Quantity expressions can be created by using the free-form linguistics interface.
  • Quantity will automatically attempt to parse an unknown unit string to its canonical form.
  • Supported units include all those specified by NIST Special Publication 811.
  • For purely numeric units, such as percents, Normal[expr] converts a Quantity object to an ordinary number.

Examples

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Basic Examples  (4)

A Quantity represents a value associated with a specific unit:

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Use to enter quantities and units:

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Compound unit expressions can also be found using :

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A unit can be a string or a product of strings:

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Valid unit specifications include a number of physical constants:

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Quantity will automatically attempt to interpret an unknown unit string:

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Scope  (6)

Applications  (2)

Properties & Relations  (12)

Possible Issues  (2)

See Also

QuantityUnit  QuantityMagnitude  UnitConvert  CompatibleUnitQ  QuantityQ  MixedMagnitude  MixedUnit  QuantityDistribution  EntityCopies  QuantityVariable  Inline Free-form Input

Tutorials

Introduced in 2012
(9.0)
| Updated in 2014
(10.0)