std::isinf
STD::ISINF
Defined in header | | |
---|---|---|
bool isinf( float arg | (1) | (since C++11) |
bool isinf( double arg | (2) | (since C++11) |
bool isinf( long double arg | (3) | (since C++11) |
bool isinf( Integral arg | (4) | (since C++11) |
1-3%29确定给定的浮点数arg
是一个正的或负的无穷大。
4%29一组重载或接受from
任何论点积分型等效于%282%29%28的参数转换为double
29%。
参数
arg | - | floating point value |
---|
返回值
true
如果arg
是无限的,false
否则。
例
二次
#include <iostream>
#include <cmath>
#include <cfloat>
int main()
{
std::cout << std::boolalpha
<< "isinf(NaN) = " << std::isinf(NAN) << '\n'
<< "isinf(Inf) = " << std::isinf(INFINITY) << '\n'
<< "isinf(0.0) = " << std::isinf(0.0) << '\n'
<< "isinf(exp(800)) = " << std::isinf(std::exp(800)) << '\n'
<< "isinf(DBL_MIN/2.0) = " << std::isinf(DBL_MIN/2.0) << '\n';
}
二次
产出:
二次
isinf(NaN) = false
isinf(Inf) = true
isinf(0.0) = false
isinf(exp(800)) = true
isinf(DBL_MIN/2.0) = false
二次
另见
fpclassify (C++11) | categorizes the given floating point value (function) |
---|---|
isfinite (C++11) | checks if the given number has finite value (function) |
isnan (C++11) | checks if the given number is NaN (function) |
isnormal (C++11) | checks if the given number is normal (function) |
c ISINF文件
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