FE_DIVBYZERO, FE_INEXACT, FE_INVALID, FE_OVERFLOW, FE_UNDERFLOW, FE_ALL_EXCEPT
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Definido no cabeçalho <cfenv> | ||
#define FE_DIVBYZERO /*implementation defined power of 2*/ | (desde C++11) | |
#define FE_INEXACT /*implementation defined power of 2*/ | (desde C++11) | |
#define FE_INVALID /*implementation defined power of 2*/ | (desde C++11) | |
#define FE_OVERFLOW /*implementation defined power of 2*/ | (desde C++11) | |
#define FE_UNDERFLOW /*implementation defined power of 2*/ | (desde C++11) | |
#define FE_ALL_EXCEPT FE_DIVBYZERO | FE_INEXACT | \ FE_INVALID | FE_OVERFLOW | \ | (desde C++11) | |
Todas essas constantes macro (exceto FE_ALL_EXCEPT) expandir para inteiros expressões constantes que são potências distintas de 2, que identificam todas as suportadas exceções de ponto flutuante. Cada macro é definida somente se for suportado.
Original:
All these macro constants (except FE_ALL_EXCEPT) expand to integer constant expressions that are distinct powers of 2, which uniquely identify all supported floating-point exceptions. Each macro is only defined if it is supported.
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O FE_ALL_EXCEPT macro constante, que se expande para o OR bit a bit de todos
FE_* outro, é sempre definida e é zero se exceções de ponto flutuante não são suportados pela implementação.Original:
The macro constant FE_ALL_EXCEPT, which expands to the bitwise OR of all other
FE_*, is always defined and is zero if floating-point exceptions are not supported by the implementation.The text has been machine-translated via Google Translate.
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Constante Original: Constant The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. | Explanation |
FE_DIVBYZERO | divisão por zero ocorreu durante a operação antes de ponto flutuante Original: division by zero occurred during the earlier floating-point operation The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
FE_INEXACT | inexato resultado: arredondamento era necessário para armazenar o resultado da operação anterior de ponto flutuante Original: inexact result: rounding was necessary to store the result of the earlier floating-point operation The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
FE_INVALID | operação inválida: a operação antes de ponto flutuante não poderia realizada Original: invalid operation: the earlier floating-point operation could not performed The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
FE_OVERFLOW | o resultado da operação de ponto flutuante anterior era grande demais para ser representável Original: the result of the earlier floating-point operation was too large to be representable The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
FE_UNDERFLOW | o resultado da operação anterior de ponto flutuante foi subnormal Original: the result of the earlier floating-point operation was subnormal The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
FE_ALL_EXCEPT | OR bit a bit de todas as exceções de ponto flutuante Original: bitwise OR of all supported floating-point exceptions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
A implementação pode definir constantes macro adicionais em
<cfenv> para identificar outras exceções de ponto flutuante. Todas as constantes de tais começam com FE_ seguido por, pelo menos, uma letra maiúscula.Original:
The implementation may define additional macro constants in
<cfenv> to identify additional floating-point exceptions. All such constants begin with FE_ followed by at least one uppercase letter.The text has been machine-translated via Google Translate.
You can help to correct and verify the translation. Click here for instructions.
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[editar]Exemplo
#include <iostream>#include <cfenv>#include <cmath> #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";}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
[editar]Veja também
(C++11) (C++11) (C++11) | define o mecanismo de tratamento de erros usado pelas funções matemáticas comuns Original: defines the error handling mechanism used by the common mathematical functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (macro constante) |
