std::fegetenv, std::fesetenv

 

C++

语言

概念

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算法库

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输入/输出库

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正则表达式库 （C++11）

原子操作库 （C++11）

线程的支持库 （C++11）

 

Numerics的图书馆

常见的数学函数

浮点环境

复数

数字阵列

伪随机数生成

编译时合理的算法 （C++11）

通用的数值运算 Original: Generic numeric operations The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

iota （C++11）

accumulate

inner_product

adjacent_difference

partial_sum

 

浮点环境

功能 Original: Functions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

feclearexcept （C++11）

fetestexcept （C++11）

feraiseexcept （C++11）

fegetexceptflag fesetexceptflag （C++11） （C++11）

fegetround fesetround （C++11） （C++11）

fegetenv fesetenv （C++11）

feholdexcept （C++11）

feupdateenv （C++11）

宏常量 Original: Macro constants 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 FE_DIVBYZERO FE_INEXACT FE_INVALID FE_OVERFLOW FE_UNDERFLOW （C++11）

FE_DOWNWARD FE_TONEAREST FE_TOWARDZERO FE_UPWARD （C++11）

FE_DFL_ENV （C++11）

 

Defined in header <cfenv>
int fegetenv( std::fenv_t* envp )	(1)	（C++11 起）
int fesetenv( const std::fenv_t* envp );	(2)	（C++11 起）

1)

试图存储状态的浮点环境中的对象指向的值，envp

Original:

Attempts to store the status of the floating-point environment in the object pointed to by envp.

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2)

尝试建立的浮点环境的envp指向的对象。对象，必须预先获得通过调用std::feholdexcept或std::fegetenv或一个浮点宏常数，如果有任何的浮点状态标志被设置在envp，他们变得​​在环境（设置，并且然后可测试与std::fetestexcept），但不提出相应的浮点异常（继续执行不间断）

Original:

Attempts to establish the floating-point environment from the object pointed to by envp. The value of that object must be previously obtained by a call to std::feholdexcept or std::fegetenv or be a floating-point macro constant. If any of the floating-point status flags are set in envp, they become set in the environment (and are then testable with std::fetestexcept), but the corresponding floating-point exceptions are not raised (execution continues uninterrupted)

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参数

envp

-

指针指向的对象类型std::fenv_t持有的地位浮点环境 Original: pointer to the object of type std::fenv_t which holds the status of the floating-point environment The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions.

返回值

​0​成功，否则返回非零值.

Original:

​0​ on success, non-zero otherwise.

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另请参阅

feholdexcept （C++11）	保存环境，清除所有状态标志，而忽略了未来所有的错误 Original: saves the environment, clears all status flags and ignores all future errors The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函数）
feupdateenv （C++11）	浮点环境恢复和提高了先前抛出异常 Original: restores the floating-point environment and raises the previously raise exceptions The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （函数）
FE_DFL_ENV （C++11）	默认的浮点环境 Original: default floating-point environment The text has been machine-translated via Google Translate. You can help to correct and verify the translation. Click here for instructions. （宏不变）