std::fetestexcept
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<tbody> </tbody>| Definido no cabeçalho <cfenv>
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int fetestexcept( int excepts ); |
(desde C++11) | |
Determina qual o subconjunto especificado de exceções de ponto flutuante estão atualmente definidas. O
excepts argumento é um OR bit a bit do flutuando macros de exceção de ponto.Original:
Determines which of the specified subset of the floating point exceptions are currently set. The argument
excepts is a bitwise OR of the flutuando macros de exceção de ponto.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Parâmetros
| excepts | - | bitmask listando as bandeiras de exceção para testar
Original: bitmask listing the exception flags to test The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
Valor de retorno
OR bit a bit das macros de ponto flutuante de exceção que são ambos incluídos no
excepts e correspondem a exceções de ponto flutuante definidos atualmente.Original:
Bitwise OR of the floating-point exception macros that are both included in
excepts and correspond to floating-point exceptions currently set.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
You can help to correct and verify the translation. Click here for instructions.
Exemplo
#include <iostream>
#include <cfenv>
#include <cmath>
#pragma STDC FENV_ACCESS ON
volatile double zero = 0.0; // volatile not needed where FENV_ACCESS is supported
volatile double 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";
} else {
std::cout << "divsion 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";
} else {
std::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";
} else {
std::cout << "invalid result not reported\n";
}
}
Saída:
1.0/0.0 = inf
division by zero reported
1.0/10 = 0.1
inexact result reported
sqrt(-1) = -nan
invalid result reported
Veja também
(C++11) |
limpa os especificados bandeiras de ponto flutuante de status Original: clears the specified floating-point status flags The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (função) |