std::setprecision
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Definido no cabeçalho <iomanip> | ||
/*unspecified*/ setprecision(int n ); | ||
Quando utilizado numa expressão out << setprecision(n) ou in >> setprecision(n), define o parâmetro do fluxo de
precision
out
ou in
exactamente n
. Original:
When used in an expression out << setprecision(n) or in >> setprecision(n), sets the
precision
parameter of the stream out
or in
to exactly n
. 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.
Índice |
[editar]Parâmetros
n | - | novo valor para a precisão Original: new value for precision The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. |
[editar]Valor de retorno
Devolve um objecto de tipo não especificado de tal forma que se
str
é o nome de um fluxo de saída de std::basic_ostream<CharT, Traits> tipo ou um fluxo de entrada de std::basic_istream<CharT, Traits> tipo, então a expressão str << setprecision(n)str >> setprecision(n) ou se comporta como se o seguinte código foi executado:Original:
Returns an object of unspecified type such that if
str
is the name of an output stream of type std::basic_ostream<CharT, Traits> or an input stream of type std::basic_istream<CharT, Traits>, then the expression str << setprecision(n) or str >> setprecision(n) behaves as if the following code was executed:The text has been machine-translated via Google Translate.
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str.precision(n);
[editar]Exemplo
#include <iostream>#include <iomanip>#include <cmath>#include <limits>int main(){constlongdouble pi =std::acos(-1.L);std::cout<<"default precision (6): "<< pi <<'\n'<<"std::precision(10): "<< std::setprecision(10)<< pi <<'\n'<<"max precision: "<< std::setprecision(std::numeric_limits<longdouble>::digits10)<< pi <<'\n';}
Saída:
default precision (6): 3.14159 std::precision(10): 3.141592654 max precision: 3.14159265358979324
[editar]Veja também
(C++11) (C++11) | alterações de formatação utilizada para ponto flutuante de I / O Original: changes formatting used for floating-point I/O The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. (função) |