std.math.ieee_flags
- multiple declarations
- Function ieeeFlags
- Struct IeeeFlags
Function ieeeFlags
Return a snapshot of the current state of the floating-point status flags.
Prototype
IeeeFlags ieeeFlags() @property;
Struct IeeeFlags
IEEE exception status flags ('sticky bits')
These flags indicate that an exceptional floating-point condition has occurred.
They indicate that a NaN
or an infinity has been generated, that a result
is inexact
, or that a signalling NaN
has been encountered. If floating-point
exceptions are enabled (unmasked), a hardware exception will be generated
instead of setting these flags.
Properties
Name | Type | Description |
---|---|---|
divByZero
[get]
|
bool |
An infinity was generated by division by zero (example: x = 3/0.0; ) |
inexact
[get]
|
bool |
The result cannot be represented exactly, so rounding occurred. |
invalid
[get]
|
bool |
A machine NaN was generated. (example: x = real.infinity * 0.0; )
|
overflow
[get]
|
bool |
An infinity was generated by overflow (example: x = real.max*2;)
|
underflow
[get]
|
bool |
A zero was generated by underflow (example: x = real.min*real.epsilon/2;)
|
Example
static void func() { int a = 10 * 10; } real a=3.5; // Set all the flags to zero resetIeeeFlags(); assert(!ieeeFlags.divByZero); // Perform a division by zero. a/=0.0L; assert(a==real.infinity); assert(ieeeFlags.divByZero); // Create a NaN a*=0.0L; assert(ieeeFlags.invalid); assert(isNaN(a)); // Check that calling func() has no effect on the // status flags. IeeeFlags f = ieeeFlags; func(); assert(ieeeFlags == f);
Authors
Walter Bright, Don Clugston, Conversion of CEPHES math library to D by Iain Buclaw