# Real128 Data Type

Holds signed 128-bit (16-byte) IEEE floating-point values in the range −1.189731495357231765085759326628007E+4932 to −3.362103143112093506262677817321753E−4932 for negative values and 3.362103143112093506262677817321753E−4932 to 1.189731495357231765085759326628007E+4932 for positive values.

## Instructions

The data type `Real128`

gives the largest and smallest possible magnitudes for a number.
`Real128`

is two times the size of `Real64`

and four times the size of `Real32`

.

- Precision
- Floating-point data types cannot store all values accurately. Operations, such as when values are compared, can cause results that you think are incorrect. See Data Type Troubleshooting for more information.
- Default value
- When you declare a variable of type
`Real128`

and do not initialize it, its default value is zero (0.0). - Zeros at the end
- The floating-point data types usually cannot show 0 characters at the end, after the decimal point. Thus numbers such as 1.4200 and 1.42 are the same value. If you must show zeros at the end, then you must use a formatter procedure.
- Type characters
`Real128`

has no type characters.

## Shared methods and properties

`Real128.Default As Real128`

- Returns the default value,
`0.0`

. `Real128.Epsilon As Real128`

- Returns the smallest difference between two values.
`Real128.IsInf(num As Real128) As Boolean`

- Returns true if
`num`

is infinity (positive or negative). Mathematical overflow is one cause of this result. `Real128.IsNaN(num As Real128) As Boolean`

- Returns true if
`num`

is not a number (Nan). “Zero divided by zero” and “square root of a negative” are two causes of this result. `Real128.IsNegInf(num As Real128) As Boolean`

- Returns true if
`num`

is negative infinity. `Real128.IsPosInf(num As Real128) As Boolean`

- Returns true if
`num`

is positive infinity. `Real128.Max As Real128`

- Returns the maximum positive value.
`Real128.Min As Real128`

- Returns the minimum negative value.
`Real128.Parse(str As String, Optional #fmt As Format) As Real128`

- Tries to parse a string that shows as a floating-point number.
- If
`#fmt`

is not given or is`#Null`

, then it uses the format of the local culture. Or you can be explicit with`Format.UserLocale`

. - If
`#fmt`

is`Format.RealLiteral`

, then it uses the format of a literal of type`Real128`

. `Real128.Size As Int`

- Returns the number of available bytes. This is always 16.

## Examples

```
Dim foo As Real128
```