MutableQuantity class

MutableQuantity supports updates to its value, dimensions and uncertainty. Changes are broadcast over the onChange stream.

Inversion

The Quantity class supports inversion through the inverse method, which returns a Quantity object that is the result of the inversion process. MiscQuantity adds to this capability with the invert method, which inverts the MiscQuantity in place without returning a object. This is possible because a MiscQuantity may have any Dimensions, whereas other Quantity subclasses have fixed Dimensions.

Implemented types

• Quantity

Constructors

MutableQuantity([Number _valueSI = Double.zero, Dimensions _dimensions = Scalar.scalarDimensions, double _ur = 0.0])

Constructs an instance, with optional SI-MKS value, dimensions and/or relative uncertainty.

MutableQuantity.from(Quantity q)

Constructs an instance from an existing Quantity.

Properties

arbitraryPrecision → bool

Whether or not this Quantity is represented using arbitrary precision.

no setter, override

cgs ↔ Number

Returns the value of this quantity in alternative CGS (or centimeter-gram-second) units. MKS (meter-kilogram-second) units are preferred.

getter/setter pair, override-getter

dimensions ↔ Dimensions

Dimensions.

getter/setter pair, override-getter

hashCode → int

Each MutableQuantity has a unique hashCode that is not value based. Therefore MutableQuantity instances with the same value and dimensions as another quantity will not have the same hash code.

no setter, override

isScalar → bool

Whether or not this Quantity has scalar dimensions, including having no angle or solid angle dimensions.

no setter, override

isScalarSI → bool

Whether or not this Quantity has scalar dimensions in the strict International System of Units (SI) sense, which allows non-zero angle and solid angle dimensions.

no setter, override

mks ↔ Number

Returns the value of this quantity in standard MKS (or meter-kilogram-second) units.

getter/setter pair, override-getter

mutable ↔ bool

Mutability can be turned on and off (defaults to true).

getter/setter pair

onChange → Stream<Quantity>

Broadcasts a snapshot of quantity whenever its value, dimensions or uncertainty changes.

no setter

preferredUnits ↔ Units?

Preferred units for display.

getter/setter pair, override-getter

relativeUncertainty ↔ double

The relative standard uncertainty in this Quantity object's value.

getter/setter pair, override-getter

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

snapshot → Quantity

Creates and returns an immutable typed Quantity that represents the value and uncertainty of this MutableQuantity at this moment.

no setter

standardUncertainty ↔ Quantity

Returns the standard uncertainty in this Quantity object's value as a typed Quantity object.

getter/setter pair, override-getter

valueSI ↔ Number

The value of the quantity in the base units, of the International System of Units (SI).

getter/setter pair, override-getter

Methods

abs() → Quantity

Converts the value of this MutableQuantity to its absolute value. Returns itself.

override

calcExpandedUncertainty(double k) → Quantity

Returns the expanded uncertainty for coverage factor, k, in this Quantity's value as a typed Quantity object.

override

compareTo(dynamic q2) → int

Compares this Quantity to q2 by comparing MKS values. The Quantities need not have the same dimensions.

override

inverse() → Quantity

Determines the inverse of the quantity represented by this object, creating and returning a Quantity object (which may have different dimensions and therefore be of a different type). This object is not modified.

override

invert() → void

Inverts this MutableQuantity, both value and dimensions, in place.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

outputText(StringBuffer buffer, {UncertaintyFormat uncertFormat = UncertaintyFormat.none, bool symbols = true, NumberFormat? numberFormat}) → void

Appends a String representation of this Quantity to the buffer using the preferred units and number format. If no preferred units have been specified, then MKS units are used. Uncertainty in the value of the Quantity is optionally shown as a plus/minus value in the same units.

override

randomSample() → Quantity

Randomly generates a Quantity from this Quantity's value and uncertainty. The uncertainty is represented by a Normal (Gaussian) continuous distribution.

override

setEqualTo(Quantity q2) → Quantity

Modifies this MutableQuantity to have the value, dimensions, uncertainty and preferred units of q2.

setValueInUnits(dynamic value, Units units) → void

Sets the this Quantity's value in the specified units. The value is expected to be a num or Number object. The units must match the current dimensions or a DimensionsException will be thrown.

sqrt() → Quantity

Returns a Quantity that represents the square root of this Quantity, in terms of both value and dimensions (for example, if this Quantity were an Area of 16 square meters, a Length of 4 meters will be returned).

override

toJson() → Map<String, dynamic>

Support dart:convert stringify.

override

toString() → String

Returns a String representation of a snapshot of this MutableQuantity .

override

valueInUnits(Units? units) → Number

Gets the Quantity's value in the specified units. If units is null, the MKS value is returned. If not null, units must have dimensions compatible with this Quantity or a DimensionsException will be thrown.

override

Operators

operator *(dynamic multiplier) → Quantity

Returns the product of this quantity and multiplier, which is expected to be either a Quantity, num or Number object. All other types will cause a QuantityException to be thrown.

override

operator +(dynamic addend) → Quantity

Returns the sum of this Quantity and addend.

override

operator -(dynamic subtrahend) → Quantity

Returns the difference of this Quantity and subtrahend or (this - q2).

override

operator /(dynamic divisor) → Quantity

Returns the quotient of this quantity and divisor, including both value and dimensions.

override

operator <(Quantity other) → bool

Determines whether on not this Quantity is less than a specified Quantity by comparing their MKS values. The two Quantities need not be of the same type or dimensions.

override

operator <=(Quantity other) → bool

Determines whether on not this Quantity is less than or equal to a specified Quantity by comparing their MKS values. The two Quantities need not be of the same type or dimensions.

override

operator ==(Object other) → bool

The equality operator.

override

operator >(Quantity other) → bool

Determines whether on not this Quantity is greater than a specified Quantity by comparing their MKS values. The two Quantities need not be of the same type or dimensions.

override

operator >=(Quantity other) → bool

Determines whether on not this Quantity is greater than or equal to a specified Quantity by comparing their MKS values. The two Quantities need not be of the same type or dimensions.

override

operator ^(dynamic exp) → Quantity

Returns this Quantity raised to the power of exponent.

override

operator unary-() → Quantity

Negates the value of this MutableQuantity and returns a reference to itself.

override