Class

UnitFrequency

A unit of measure for frequency.

Declaration

class UnitFrequency : Dimension

Overview

You typically use instances of NSUnitFrequency to represent specific quantities of frequency using the NSMeasurement class.

Frequency

Frequency is a quantity of occurrences for a repeating event over time. The SI unit for frequency is the hertz (Hz), which is a derived as one occurrence per second (1Hz = 1 / 1s).

The NSUnitFrequency class defines its base unit as hertz, and provides the following units, which are initialized using UnitConverterLinear converters with the specified coefficients:

Name

Method

Symbol

Coefficient

Terahertz

terahertz

THz

1e12

Gigahertz

gigahertz

GHz

1e9

Megahertz

megahertz

MHz

1000000.0

Kilohertz

kilohertz

kHz

1000.0

Hertz

hertz

Hz

1

Millihertz

millihertz

mHz

0.001

Microhertz

microhertz

µHz

0.000001

Nanohertz

nanohertz

nHz

1e-9

Topics

Accessing Predefined Units

class var terahertz: UnitFrequency

Returns the terahertz unit of frequency.

class var gigahertz: UnitFrequency

Returns the gigahertz unit of frequency.

class var megahertz: UnitFrequency

Returns the megahertz unit of frequency.

class var kilohertz: UnitFrequency

Returns the kilohertz unit of frequency.

class var hertz: UnitFrequency

Returns the hertz unit of frequency.

class var millihertz: UnitFrequency

Returns the millihertz unit of frequency.

class var microhertz: UnitFrequency

Returns the microhertz unit of frequency.

class var nanohertz: UnitFrequency

Returns the nanohertz unit of frequency.

Relationships

Inherits From

See Also

Time and Motion

class UnitAcceleration

A unit of measure for acceleration.

class UnitDuration

A unit of measure for duration of time.

class UnitSpeed

A unit of measure for speed.

Beta Software

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