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      std::feclearexcept

      From cppreference.com
      <cpp‎ |numeric‎ |fenv
       
       
       
      Floating-point environment
      Functions
      feclearexcept
      (C++11)
      (C++11)(C++11)
      (C++11)(C++11)
      Macro constants
      (C++11)
       
      Defined in header<cfenv>
      int feclearexcept(int excepts);
      (since C++11)

      Attempts to clear the floating-point exceptions that are listed in the bitmask argumentexcepts, which is a bitwise OR of thefloating point exception macros.

      Contents

      [edit]Parameters

      excepts - bitmask listing the exception flags to clear

      [edit]Return value

      0 if all indicated exceptions were successfully cleared or ifexcepts is zero. Returns a non-zero value on error.

      [edit]Example

      [edit]
      Run this code
      #include <cfenv>#include <cmath>#include <iostream> // #pragma STDC FENV_ACCESS ON volatiledouble zero=0.0;// volatile not needed where FENV_ACCESS is supportedvolatiledouble one=1.0;// volatile not needed where FENV_ACCESS is supported int main(){    std::feclearexcept(FE_ALL_EXCEPT);std::cout<<"1.0/0.0 = "<<1.0/ zero<<'\n';if(std::fetestexcept(FE_DIVBYZERO))std::cout<<"division by zero reported\n";elsestd::cout<<"division by zero not reported\n";     std::feclearexcept(FE_ALL_EXCEPT);std::cout<<"1.0/10 = "<< one/10<<'\n';if(std::fetestexcept(FE_INEXACT))std::cout<<"inexact result reported\n";elsestd::cout<<"inexact result not reported\n";     std::feclearexcept(FE_ALL_EXCEPT);std::cout<<"sqrt(-1) = "<<std::sqrt(-1)<<'\n';if(std::fetestexcept(FE_INVALID))std::cout<<"invalid result reported\n";elsestd::cout<<"invalid result not reported\n";}

      Possible output:

      1.0/0.0 = infdivision by zero reported1.0/10 = 0.1inexact result reportedsqrt(-1) = -naninvalid result reported

      [edit]See also

      determines which of the specified floating-point status flags are set
      (function)[edit]
      C documentation forfeclearexcept
      Retrieved from "https://en.cppreference.com/mwiki/index.php?title=cpp/numeric/fenv/feclearexcept&oldid=95618"

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