std::isfinite
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Defined in header
<cmath>
(1)
bool isfinite( float num );
(since C++11) bool isfinite( double num );
(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 >
(S)
(since C++26)
constexpr typename /*deduced-simd-t*/<V>::mask_type
Defined in header
<cmath>
template< class Integer >
bool isfinite( Integer num );
(A)
(since C++11) bool isfinite( Integer num );
(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.)
A) Additional overloads are provided for all integer types, which are treated as double.
[edit] 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
[edit] 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()).[edit] 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)).
[edit] Examples
Run this code
#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
[edit] See also
C documentation for isfinite