Class

NSUnitDuration

A unit of measure for duration of time.

Declaration

@interface NSUnitDuration : NSDimension

Overview

You typically use instances of NSUnitDuration to represent specific quantities of planar angle using the NSMeasurement class.

Duration

Duration is a quantity of time. The SI unit for time is the second (sec), which is defined in terms of the radioactivity of a cesium-133 atom. Duration is also commonly expressed in terms of minutes (min) and hours (hr).

The NSUnitDuration class defines its base unit as seconds, and provides the following units, which are initialized using NSUnitConverterLinear converters with the specified coefficients:

Name

Method

Symbol

Coefficient

Seconds

seconds

sec

1

Minutes

minutes

min

60

Hours

hours

hr

3600

Topics

Accessing the Base Unit

+ baseUnit

Returns the base unit of duration. Equal to seconds.

Accessing Predefined Units

seconds

Returns the second unit of duration.

minutes

Returns the minute unit of duration.

hours

Returns the hour unit of duration.

Relationships

Inherits From

Conforms To

See Also

Time and Motion

NSUnitAcceleration

A unit of measure for acceleration.

NSUnitFrequency

A unit of measure for frequency.

NSUnitSpeed

A unit of measure for speed.