std::isfinite
Defined in header <cmath> | ||
|---|---|---|
bool isfinite( float num ); bool isfinite( double num ); bool isfinite( long double num ); | (1) |
(since C++11) (until C++23) |
constexpr bool isfinite( /*floating-point-type*/ num ); | (since C++23) | |
| SIMD overload (since C++26) | ||
Defined in header <simd> | ||
template< /*math-floating-point*/ V > constexpr typename /*deduced-simd-t*/<V>::mask_type isfinite ( const V& v_num ); | (S) | (since C++26) |
| Additional overloads | ||
Defined in header <cmath> | ||
template< class Integer > bool isfinite( Integer num ); | (A) | (since C++11) (constexpr since C++23) |
1) Determines if the given floating point number
num has finite value i.e. it is normal, subnormal or zero, but not infinite or NaN. The library provides overloads for all cv-unqualified floating-point types as the type of the parameter num.(since C++23)
S) The SIMD overload performs an element-wise std::isfinite on v_num. (See math-floating-point and deduced-simd-t for their definitions.) | (since C++26) |
A) Additional overloads are provided for all integer types, which are treated as double.
Parameters
| num | - | floating-point or integer value |
| v_num | - | a data-parallel object of std::basic_simd specialization where its element type is a floating-point type |
Return value
1)
true if num has finite value, false otherwise.
S) A data-parallel mask object where the ith element equals
true if v_num[i] has finite value or false otherwise for all i in the range [0, v_num.size()).Notes
The additional overloads are not required to be provided exactly as (A). They only need to be sufficient to ensure that for their argument num of integer type, std::isfinite(num) has the same effect as std::isfinite(static_cast<double>(num)).
Examples
#include <cfloat>
#include <cmath>
#include <iostream>
int main()
{
std::cout << std::boolalpha
<< "isfinite(NaN) = " << std::isfinite(NAN) << '\n'
<< "isfinite(Inf) = " << std::isfinite(INFINITY) << '\n'
<< "isfinite(-Inf) = " << std::isfinite(-INFINITY) << '\n'
<< "isfinite(HUGE_VAL) = " << std::isfinite(HUGE_VAL) << '\n'
<< "isfinite(0.0) = " << std::isfinite(0.0) << '\n'
<< "isfinite(exp(800)) = " << std::isfinite(std::exp(800)) << '\n'
<< "isfinite(DBL_MIN/2.0) = " << std::isfinite(DBL_MIN / 2.0) << '\n';
}
Output:
isfinite(NaN) = false isfinite(Inf) = false isfinite(-Inf) = false isfinite(HUGE_VAL) = false isfinite(0.0) = true isfinite(exp(800)) = false isfinite(DBL_MIN/2.0) = true
See also
|
(C++11) | categorizes the given floating-point value (function) |
|
(C++11) | checks if the given number is infinite (function) |
|
(C++11) | checks if the given number is NaN (function) |
|
(C++11) | checks if the given number is normal (function) |
C documentation for isfinite |
|
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