std::feraiseexcept

 

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Floating-point environment

Functions

feclearexcept (C++11)

fetestexcept (C++11)

feraiseexcept (C++11)

fegetexceptflagfesetexceptflag (C++11)(C++11)

fegetroundfesetround (C++11)(C++11)

fegetenvfesetenv (C++11)(C++11)

feholdexcept (C++11)

feupdateenv (C++11)

Macro constants

FE_ALL_EXCEPTFE_DIVBYZEROFE_INEXACTFE_INVALIDFE_OVERFLOWFE_UNDERFLOW (C++11)(C++11)(C++11)(C++11)(C++11)(C++11)

FE_DOWNWARDFE_TONEARESTFE_TOWARDZEROFE_UPWARD (C++11)(C++11)(C++11)(C++11)

FE_DFL_ENV (C++11)

 

Defined in header <cfenv>
int feraiseexcept(int excepts );		(since C++11)

Attempts to raise all floating point exceptions listed in excepts (a bitwise OR of the floating point exception macros). If one of the exceptions is FE_OVERFLOW or FE_UNDERFLOW, this function may additionally raise FE_INEXACT. The order in which the exceptions are raised is unspecified, except that FE_OVERFLOW and FE_UNDERFLOW are always raised before FE_INEXACT.

Parameters

excepts

-

bitmask listing the exception flags to raise

Return value

​0​ if all listed exceptions were raised, non-zero value otherwise.

Example

Run this code

#include <cfenv>#include <iostream>   // #pragma STDC FENV_ACCESS ON   int main(){std::feclearexcept(FE_ALL_EXCEPT);constint r = std::feraiseexcept(FE_UNDERFLOW|FE_DIVBYZERO);std::cout<<"Raising divbyzero and underflow simultaneously "<<(r ?"fails":"succeeds")<<" and results in\n";   constint e =std::fetestexcept(FE_ALL_EXCEPT);if(e &FE_DIVBYZERO)std::cout<<"division by zero\n";if(e &FE_INEXACT)std::cout<<"inexact\n";if(e &FE_INVALID)std::cout<<"invalid\n";if(e &FE_UNDERFLOW)std::cout<<"underflow\n";if(e &FE_OVERFLOW)std::cout<<"overflow\n";}

Output:

Raising divbyzero and underflow simultaneously succeeds and results in division by zero underflow

See also

feclearexcept (C++11)	clears the specified floating-point status flags (function)
fetestexcept (C++11)	determines which of the specified floating-point status flags are set (function)
C documentation for feraiseexcept