FLT_EVAL_METHOD
Defined in header <cfloat> | | |
|---|---|---|
#define FLT_EVAL_METHOD /* implementation defined */ | | (since C++11) |
指定执行除赋值和强制转换以外的所有浮点算术操作的精度。
Value | Explanation |
|---|---|
negative values except -1 | implementation-defined behavior |
-1 | the default precision is not known |
0 | all operations and constants evaluate in the range and precision of the type used. Additionally, float_t and double_t are equivalent to float and double respectively |
1 | all operations and constants evaluate in the range and precision of double. Additionally, both float_t and double_t are equivalent to double |
2 | all operations and constants evaluate in the range and precision of long double. Additionally, both float_t and double_t are equivalent to long double |
注记
不管…的价值FLT_EVAL_METHOD，任何浮点表达式都可能是承包，也就是说，如果所有中间结果都有无限的范围和精度，除非#语用STDC FP_CONTRACT关闭%29。
转换和赋值剥离任何无关的范围和精度：这是一种将值从扩展精度FPU寄存器存储到标准大小的内存位置的行为模型。
另见
C.FLT文件[医]埃瓦尔[医]方法
*。
© cppreference.com在CreativeCommonsAttribution下授权-ShareAlike未移植许可v3.0。
本文档系腾讯云开发者社区成员共同维护，如有问题请联系 cloudcommunity@tencent.com
