A double-precision, floating-point value type.
SDK
- Xcode 6.0.1+
Framework
- Swift Standard Library
Declaration
@frozen struct Double
Structure
Double
Topics
Converting Integers
init<Source>(Source)Creates a new value, rounded to the closest possible representation.
init(Int)Creates a new value, rounded to the closest possible representation.
Converting Strings
init?<S>(S)Creates a new instance from the given string.
Converting Floating-Point Values
init<Source>(Source)Creates a new instance from the given value, rounded to the closest possible representation.
init(Double)Creates a new instance initialized to the given value.
init(Float)Creates a new instance that approximates the given value.
init(Float80)Creates a new instance that approximates the given value.
init(CGFloat)Creates a new instance initialized to the given value.
init(sign: FloatingPointSign, exponent: Int, significand: Double)Creates a new value from the given sign, exponent, and significand.
init(signOf : Double, magnitudeOf : Double)Creates a new floating-point value using the sign of one value and the magnitude of another.
init<Source>(Source)Creates a new value, rounded to the closest possible representation.
Converting with No Loss of Precision
These initializers result in nil if the value passed can't be represented without any loss of precision.
init?<Source>(exactly: Source)Creates a new instance from the given value, if it can be represented exactly.
init?<Source>(exactly: Source)Creates a new value, if the given integer can be represented exactly.
init?(exactly: Double)Creates a new instance initialized to the given value, if it can be represented without rounding.
init?(exactly: Float)Creates a new instance initialized to the given value, if it can be represented without rounding.
init?(exactly: Float80)Creates a new instance initialized to the given value, if it can be represented without rounding.
Creating a Random Value
static func random(in: Range<Double>) -> DoubleReturns a random value within the specified range.
static func random<T>(in: Range<Double>, using: inout T) -> DoubleReturns a random value within the specified range, using the given generator as a source for randomness.
static func random(in: ClosedRange<Double>) -> Double Returns a random value within the specified range.
static func random<T>(in: ClosedRange<Double>, using: inout T) -> DoubleReturns a random value within the specified range, using the given generator as a source for randomness.
Performing Calculations
Floating-Point Operators for Double
Perform arithmetic and bitwise operations or compare values.
func addingProduct (Double, Double) -> DoubleReturns the result of adding the product of the two given values to this value, computed without intermediate rounding.
func addProduct (Double, Double)Adds the product of the two given values to this value in place, computed without intermediate rounding.
func squareRoot () -> DoubleReturns the square root of the value, rounded to a representable value.
func formSquareRoot ()Replaces this value with its square root, rounded to a representable value.
func remainder(dividingBy : Double) -> DoubleReturns the remainder of this value divided by the given value.
func formRemainder (dividingBy : Double)Replaces this value with the remainder of itself divided by the given value.
func truncatingRemainder (dividingBy : Double) -> DoubleReturns the remainder of this value divided by the given value using truncating division.
func formTruncatingRemainder (dividingBy : Double)Replaces this value with the remainder of itself divided by the given value using truncating division.
func negate()Replaces this value with its additive inverse.
Rounding Values
func rounded() -> DoubleReturns this value rounded to an integral value using “schoolbook rounding.”
func rounded(FloatingPointRoundingRule) -> Double Returns this value rounded to an integral value using the specified rounding rule.
func round()Rounds this value to an integral value using “schoolbook rounding.”
func round(FloatingPointRoundingRule) Rounds the value to an integral value using the specified rounding rule.
Comparing Values
Floating-Point Operators for Double
Perform arithmetic and bitwise operations or compare values.
func isEqual (to: Double) -> BoolReturns a Boolean value indicating whether this instance is equal to the given value.
func isLess (than: Double) -> BoolReturns a Boolean value indicating whether this instance is less than the given value.
func isLessThanOrEqualTo (Double) -> BoolReturns a Boolean value indicating whether this instance is less than or equal to the given value.
func isTotallyOrdered (belowOrEqualTo : Double) -> BoolReturns a Boolean value indicating whether this instance should precede or tie positions with the given value in an ascending sort.
static func minimum(Double, Double) -> DoubleReturns the lesser of the two given values.
static func minimumMagnitude (Double, Double) -> DoubleReturns the value with lesser magnitude.
static func maximum(Double, Double) -> DoubleReturns the greater of the two given values.
static func maximumMagnitude (Double, Double) -> DoubleReturns the value with greater magnitude.
Finding the Sign and Magnitude
var magnitude: DoubleThe magnitude of this value.
var sign: FloatingPointSign The sign of the floating-point value.
typealias Double.Magnitude A type that can represent the absolute value of any possible value of this type.
Querying a Double
var ulp: DoubleThe unit in the last place of this value.
var significand: DoubleThe significand of the floating-point value.
var exponent: IntThe exponent of the floating-point value.
var nextUp : DoubleThe least representable value that compares greater than this value.
var nextDown : DoubleThe greatest representable value that compares less than this value.
var binade: DoubleThe floating-point value with the same sign and exponent as this value, but with a significand of 1.0.
Accessing Numeric Constants
static var pi: DoubleThe mathematical constant pi.
static var infinity: DoublePositive infinity.
static var greatestFiniteMagnitude : DoubleThe greatest finite number representable by this type.
static var nan: DoubleA quiet NaN (“not a number”).
static var signalingNaN : DoubleA signaling NaN (“not a number”).
static var ulpOfOne : DoubleThe unit in the last place of 1.0.
static var leastNonzeroMagnitude : DoubleThe least positive number.
static var leastNormalMagnitude : DoubleThe least positive normal number.
static var zero: DoubleThe zero value.
Working with Binary Representation
var bitPattern : UInt64The bit pattern of the value’s encoding.
var significandBitPattern : UInt64The raw encoding of the value’s significand field.
var significandWidth : IntThe number of bits required to represent the value’s significand.
var exponentBitPattern : UIntThe raw encoding of the value’s exponent field.
static var significandBitCount : IntThe available number of fractional significand bits.
static var exponentBitCount : IntThe number of bits used to represent the type’s exponent.
static var radix: IntThe radix, or base of exponentiation, for this floating-point type.
init(bitPattern : UInt64)Creates a new value with the given bit pattern.
init(sign: FloatingPointSign, exponentBitPattern : UInt, significandBitPattern : UInt64)Creates a new instance from the specified sign and bit patterns.
init(nan: Double.RawSignificand, signaling: Bool)Creates a NaN (“not a number”) value with the specified payload.
typealias Double.Exponent A type that can represent any written exponent.
typealias Double.RawSignificand A type that represents the encoded significand of a value.
Querying a Double's State
var isZero : BoolA Boolean value indicating whether the instance is equal to zero.
var isFinite : BoolA Boolean value indicating whether this instance is finite.
var isInfinite : BoolA Boolean value indicating whether the instance is infinite.
var isNaN : BoolA Boolean value indicating whether the instance is NaN (“not a number”).
var isSignalingNaN : BoolA Boolean value indicating whether the instance is a signaling NaN.
var isNormal : BoolA Boolean value indicating whether this instance is normal.
var isSubnormal : BoolA Boolean value indicating whether the instance is subnormal.
var isCanonical : BoolA Boolean value indicating whether the instance’s representation is in the canonical form.
var floatingPointClass : FloatingPointClassification The classification of this value.
Encoding and Decoding Values
func encode(to: Encoder)Encodes this value into the given encoder.
init(from: Decoder)Creates a new instance by decoding from the given decoder.
Creating a Range
static func ..< (Double, Double) -> Range<Double>Returns a half-open range that contains its lower bound but not its upper bound.
static func ... (Double, Double) -> ClosedRange<Double> Returns a closed range that contains both of its bounds.
Describing a Double
var description: StringA textual representation of the value.
var debugDescription : StringA textual representation of the value, suitable for debugging.
var customMirror : MirrorA mirror that reflects the Double instance.
var hashValue : IntThe hash value.
func hash(into: inout Hasher)Hashes the essential components of this value by feeding them into the given hasher.
Using a Double as a Data Value
init?(from: MLDataValue) Creates a double from another double wrapped in a data value.
var dataValue : MLDataValue The double wrapped in a data value.
static var dataValueType : MLDataValue.ValueType The underlying type a double uses when it wraps itself in a data value.
Infrequently Used Functionality
init()Creates a value initialized to zero.
init(floatLiteral : Double)Creates a new value from the given floating-point literal.
init(integerLiteral : Int64)Creates a new value from the given integer literal.
init(integerLiteral : Double)Creates an instance initialized to the specified integer value.
func advanced(by: Double) -> DoubleReturns a new value advanced by the given distance.
func distance(to: Double) -> DoubleReturns the distance from this value to the specified value.
func write<Target>(to: inout Target)Writes a textual representation of this instance into the given output stream.
SIMD-Supporting Types
struct Double.SIMD2Storage Storage for a vector of two floating-point values.
struct Double.SIMD4Storage Storage for a vector of four floating-point values.
struct Double.SIMD8Storage Storage for a vector of eight floating-point values.
struct Double.SIMD16Storage Storage for a vector of 16 floating-point values.
struct Double.SIMD32Storage Storage for a vector of 32 floating-point values.
struct Double.SIMD64Storage Storage for a vector of 64 floating-point values.
Deprecated
var customPlaygroundQuickLook : _PlaygroundQuickLook A custom playground Quick Look for the Double instance.
init(NSNumber)DeprecatedType Aliases
typealias Double.FloatLiteralType A type that represents a floating-point literal.
typealias Double.IntegerLiteralType A type that represents an integer literal.
typealias Double.RawExponent A type that represents the encoded exponent of a value.
typealias Double.Stride A type that represents the distance between two values.
Instance Properties
Instance Methods
Relationships
Conforms To
See Also
Standard Library
struct IntA signed integer value type.
struct StringA Unicode string value that is a collection of characters.
struct ArrayAn ordered, random-access collection.
struct DictionaryA collection whose elements are key-value pairs.
Swift Standard Library
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