Units mixin

A unit is a particular physical quantity, defined and adopted by convention, with which other particular quantities of the same kind (dimensions) are compared to express their value.

The Units class represents a unit and includes a name (plural), an optional intermediate abbreviation, an optional symbol and an optional singular form. A Units object stores a conversion value (to convert a value to SI-MKS units) and dimensions.

Abstract Units Mixin

This class is designed to be used as a mixin. In this way typed units wind up being quantities themselves, extending the associated quantity type and mixing in units to represent themselves as units objects (e.g., LengthUnits extends Length with Units). This is consistent with the definition of units as quantities with specific values and means also that units objects are quantity objects and can be used as quantity parameters.

'Units' vs. 'Unit'

Precisely speaking, quantities are expressed as multiples of a particular unit (singular, not plural). However, when the quantity's absolute value is greater than 1, the unit is pluralized when spoken. For example, one says 'five meters,' not 'five of the meter unit' or something along those lines. Therefore, to make units easier to work with and program, this package calls this class Units and not Unit and defines all static unit objects with plural names (e.g., meters vs. meter). This leads to a more natural expression upon Quantity object creation and value manipulation.

Mixin Applications

Properties

abbrev1 ↔ String?: The primary abbreviation for the units.
getter/setter pair
abbrev2 ↔ String?: A secondary abbreviation for the units.
getter/setter pair
alternateName → String?: Returns the alternate name for the units. This may be a non-standard representation. If no alternate name exists, then null is returned.
no setter
convToMKS ↔ Number: Multiply by this value to convert a Quantity in these units to SI-MKS units.
getter/setter pair
hashCode → int: All units have a unique name.
no setteroverride
metricBase ↔ bool: Whether these units are considered a base metric unit.
getter/setter pair
name ↔ String: The name of the units (plural).
getter/setter pair
offset ↔ double: The offset of this unit from zero in the metric unit scale.
getter/setter pair
quantityType → Type: The Type to which the Units apply
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
singular ↔ String?: The name of the units in singular form.
getter/setter pair

Methods

atto() → Units: Returns the derived Units having the 10^-18 prefix, atto (a).
centi() → Units: Returns the derived Units having the 10^-2 (i.e., 0.01) prefix, centi (c).
deci() → Units: Returns the derived Units having the 10^-1 (i.e., 0.1) prefix, deci (d).
deka() → Units: Returns the derived Units having the 10^1 (i.e. 10) prefix, deka (da).
derive(String fullPrefix, String abbrevPrefix, double conv) → Units: Derive Units using this Units object as the base.
exa() → Units: Returns the derived Units having the 10^18 prefix, exa (E).
femto() → Units: Returns the derived Units having the 10^-15 prefix, femto (f).
fromMks(dynamic mks) → Number: Calculates and returns the value in the units represented by this Units object of mks (that is expected to be in SI-MKS units). The method accepts a num or Number object; any other type will cause a QuantityException.
getShortestName(bool sing) → String: Returns the shortest name for the units. This will be the first non-null name found when inspecting secondary abbreviation, primary abbreviation and full name, in that order. If sing is true and no symbol or alternate name are available then the singular version of the name will be returned.
giga() → Units: Returns the derived Units having the 10^9 prefix, giga (G).
hecto() → Units: Returns the derived Units having the 10^2 (i.e., 100) prefix, hecto (h).
kilo() → Units: Returns the derived Units having the 10^3 (i.e., 1000) prefix, kilo (k).
mega() → Units: Returns the derived Units having the 10^6 prefix, mega (M).
micro() → Units: Returns the derived Units having the 10^-6 prefix, micro (the symbol mu).
milli() → Units: Returns the derived Units having the 10^-3 (i.e., 0.001) prefix, milli (m).
nano() → Units: Returns the derived Units having the 10^-9 prefix, nano (n).
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
peta() → Units: Returns the derived Units having the 10^15 prefix, peta (P).
pico() → Units: Returns the derived Units having the 10^-12 prefix, pico (p).
tera() → Units: Returns the derived Units having the 10^12 prefix, tera (T).
toMks(dynamic value) → Number: Calculates and returns the value in SI-MKS units of the specified value (that is implicitly in these units). The method expects value to be a num or Number object; any other type will cause a QuantityException.
toString() → String: Returns a String representation of the Units in the following format:
override
yocto() → Units: Returns the derived Units having the 10^-24 prefix, yocto (y).
yotta() → Units: Returns the derived Units having the 10^24 prefix, yotta (Y).
zepto() → Units: Returns the derived Units having the 10^-21 prefix, zepto (z).
zetta() → Units: Returns the derived Units having the 10^21 prefix, zetta (Z).

Operators

operator ==(dynamic obj) → bool: Two units are considered equal if their conversions to MKS are equal and they have the same singular name.
override