[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] Reference for unit 'sysutils' (#rtl)

# TDoubleHelper

[Properties (by Name)] [Methods (by Name)] [Events (by Name)]

Helper for Double floating point type

## Declaration

Source position: syshelph.inc line 263

 type TDoubleHelper = type helper public Const Epsilon = Epsilon; = 4.9406564584124654418e-324 Precision for this floating point type MaxValue = MaxValue; = 1.7976931348623157081e+308 Largest possible value for the Double floating point type MinValue = MinValue; = - 1.7976931348623157081e+308 Smallest (negative) possible value for the Double floating point type PositiveInfinity = PositiveInfinity; = 1.0 / 0.0 Positive infinity as represented by a Double floating point type NegativeInfinity = NegativeInfinity; = (- 1.0) / (0.0) Negative infinity as represented by a Double floating point type NaN = NaN; = 0.0 / 0.0 Representation of NaN (Not a Number) class function IsInfinity(); Check whether a value is positive or negative infinity. class function IsNan(); Check whether a value equals NaN. class function IsNegativeInfinity(); Check whether a value is negative infinity. class function IsPositiveInfinity(); Check whether a value is positive infinity. class function Parse(); Convert a string to a floating point value class function Size; Size (in bytes) of a Double-sized floating point value. class function ToString(); Convert a Double-sized floating point value to a string class function TryParse(); Try to convert a string to a Double-sized floating point value. procedure BuildUp(); Build a Double-sized floating point from its composing parts function Exponent; Exponent of the floating-point value function Fraction; Fraction of the floating-point value function Mantissa; Mantissa of the floating-point function SpecialType; Return the type of the Double-sized floating point value property Bytes []: Byte; [rw] Indexed access to the individual bytes of the floating point value property Words []: Word; [rw] Indexed access to the words that make up the floating point value property Sign: Boolean; [rw] Sign of the floating point value property Exp: QWord; [rw] The bit pattern of the exponent as stored in memory. property Frac: QWord; [rw] Bitpattern that makes up the fractional part. end;

## Inheritance

 TDoubleHelper Helper for Double floating point type

## Description

TDoubleHelper is the helper type for the Double-sized floating point type. It contains some conversion methods, as well as access to the low-level structure of the floating-point representation of a Double.

## See also

 TDoubleHelper Helper for Double floating point type TExtendedHelper Helper for Extended floating point type