std::fegetround, std::fesetround
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<metanoindex/>
<tbody> </tbody>| Definido no cabeçalho <cfenv>
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int fesetround( int round ) |
(1) | (desde C++11) |
int fegetround() |
(2) | (desde C++11) |
1)
Tentativas para estabelecer o sentido de arredondamento de ponto flutuante igual à
round argumento, que se espera que seja um dos flutuando macros arredondamento de pontos. Original:
Attempts to establish the floating-point rounding direction equal to the argument
round, which is expected to be one of the flutuando macros arredondamento de pontos. 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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2)
Retorna o valor da flutuando macro arredondamento ponto que corresponde à direcção de arredondamento correntes.
Original:
Returns the value of the flutuando macro arredondamento ponto that corresponds to the current rounding direction.
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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Parâmetros
| round | - | direção de arredondamento, um dos flutuando macros arredondamento de pontos
Original: rounding direction, one of flutuando macros arredondamento de pontos 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
1)
0 em caso de sucesso, não-zero, caso contrário.Original:
0 on success, non-zero otherwise.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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2)
o flutuando macro arredondamento ponto descrevendo a direcção arredondamento corrente ou um valor negativo se a direcção não pode ser determinada
Original:
the flutuando macro arredondamento ponto describing the current rounding direction or a negative value if the direction cannot be determined
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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Exemplo
#include <cmath>
#include <cfenv>
#include <iostream>
int main()
{
#pragma STDC FENV_ACCESS ON
std::fesetround(FE_DOWNWARD);
std::cout << "rounding using FE_DOWNWARD: \n" << std::fixed
<< " 12.0 -> " << std::nearbyint(12.0) << '\n'
<< " 12.1 -> " << std::nearbyint(12.1) << '\n'
<< "-12.1 -> " << std::nearbyint(-12.1) << '\n'
<< " 12.5 -> " << std::nearbyint(12.5) << '\n'
<< " 12.9 -> " << std::nearbyint(12.9) << '\n'
<< "-12.9 -> " << std::nearbyint(-12.9) << '\n'
<< " 13.0 -> " << std::nearbyint(13.0) << '\n';
std::fesetround(FE_TONEAREST);
std::cout << "rounding using FE_TONEAREST: \n"
<< " 12.0 -> " << std::nearbyint(12.0) << '\n'
<< " 12.1 -> " << std::nearbyint(12.1) << '\n'
<< "-12.1 -> " << std::nearbyint(-12.1) << '\n'
<< " 12.5 -> " << std::nearbyint(12.5) << '\n'
<< " 12.9 -> " << std::nearbyint(12.9) << '\n'
<< "-12.9 -> " << std::nearbyint(-12.9) << '\n'
<< " 13.0 -> " << std::nearbyint(13.0) << '\n';
}
Saída:
rounding using FE_DOWNWARD:
12.0 -> 12.000000
12.1 -> 12.000000
-12.1 -> -13.000000
12.5 -> 12.000000
12.9 -> 12.000000
-12.9 -> -13.000000
13.0 -> 13.000000
rounding using FE_TONEAREST:
12.0 -> 12.000000
12.1 -> 12.000000
-12.1 -> -12.000000
12.5 -> 12.000000
12.9 -> 13.000000
-12.9 -> -13.000000
13.0 -> 13.000000
Veja também
(C++11) |
número inteiro mais próximo utilizando o modo de arredondamento correntes Original: nearest integer using current rounding mode The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (função) |
(C++11) (C++11) (C++11) |
número inteiro mais próximo usando o modo de arredondamento atual com exceção se o resultado é diferente Original: nearest integer using current rounding mode with exception if the result differs The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (função) |