Standard library header <cfloat>
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Standard library headers 
 
 
 
 
 
 
 
 
 
 <cfloat>
 <compare> (C++20)
 <contracts> (C++26)
 <coroutine> (C++20)
 <cstdint> (C++11)
 <source_location> (C++20)
 <stdfloat> (C++23)
 <version> (C++20)
 <concepts> (C++20)
 <debugging> (C++26)
 <stacktrace> (C++23)
 <system_error> (C++11)
 <memory_resource> (C++17)
 <scoped_allocator> (C++11)
 <type_traits> (C++11)
 <ratio> (C++11)
 <any> (C++17)
 <bit> (C++20)
 <charconv> (C++17)
 <expected> (C++23)
 <format> (C++20)
 <optional> (C++17)
 <stdbit.h> (C++26)
 <tuple> (C++11)
 <typeindex> (C++11)
 <variant> (C++17)
 <array> (C++11)
 <flat_map> (C++23)
 <flat_set> (C++23)
 <forward_list> (C++11)
 <hive> (C++26)
 <mdspan> (C++23)
 <span> (C++20)
 <unordered_map> (C++11)
 <unordered_set> (C++11)
 <generator> (C++23)
 <ranges> (C++20)
 <cuchar> (C++11)
 <string_view> (C++17)
 <codecvt> (C++11/17/26*)
 <regex> (C++11)
 <cfenv> (C++11)
 <linalg> (C++26)
 <numbers> (C++20)
 <random> (C++11)
 <simd> (C++26)
 <stdckdint.h> (C++26)
 <chrono> (C++11)
 <ccomplex> (C++11/17/20*)
 <ciso646> (until C++20)
 <cstdalign> (C++11/17/20*)
 <cstdbool> (C++11/17/20*)
 <ctgmath> (C++11/17/20*)
 <cinttypes> (C++11)
 <filesystem> (C++17)
 <print> (C++23)
 <spanstream> (C++23)
 <strstream> (C++98/26*)
 <syncstream> (C++20)
 <atomic> (C++11)
 <barrier> (C++20)
 <condition_variable> (C++11)
 <future> (C++11)
 <hazard_pointer> (C++26)
 <latch> (C++20)
 <mutex> (C++11)
 <rcu> (C++26)
 <semaphore> (C++20)
 <shared_mutex> (C++14)
 <stdatomic.h> (C++23)
 <stop_token> (C++20)
 <thread> (C++11)
 <execution> (C++17)
This header was originally in the C standard library as <float.h>.
This header is part of the type support library, in particular, it is a part of the C numeric limits interface.
[edit] Macros
FLT_RADIX
(macro constant) [edit]
DECIMAL_DIG
(C++11)
(macro constant) [edit]
FLT_DECIMAL_DIGDBL_DECIMAL_DIGLDBL_DECIMAL_DIG
(C++17)
(macro constant) [edit]
FLT_MINDBL_MINLDBL_MIN
(macro constant) [edit]
FLT_TRUE_MINDBL_TRUE_MINLDBL_TRUE_MIN
(C++17)
(macro constant) [edit]
FLT_MAXDBL_MAXLDBL_MAX
(macro constant) [edit]
FLT_EPSILONDBL_EPSILONLDBL_EPSILON
(macro constant) [edit]
FLT_DIGDBL_DIGLDBL_DIG
(macro constant) [edit]
FLT_MANT_DIGDBL_MANT_DIGLDBL_MANT_DIG
(macro constant) [edit]
FLT_MIN_EXPDBL_MIN_EXPLDBL_MIN_EXP
(macro constant) [edit]
FLT_MIN_10_EXPDBL_MIN_10_EXPLDBL_MIN_10_EXP
(macro constant) [edit]
FLT_MAX_EXPDBL_MAX_EXPLDBL_MAX_EXP
(macro constant) [edit]
FLT_MAX_10_EXPDBL_MAX_10_EXPLDBL_MAX_10_EXP
(macro constant) [edit]
FLT_HAS_SUBNORMDBL_HAS_SUBNORMLDBL_HAS_SUBNORM
(C++17)
-1 – indeterminable, 0 – absent, 1 – present
(macro constant) [edit]
[edit] Synopsis
#define FLT_ROUNDS /* see definition */ #define FLT_EVAL_METHOD /* see definition */ #define FLT_HAS_SUBNORM /* see definition */ #define DBL_HAS_SUBNORM /* see definition */ #define LDBL_HAS_SUBNORM /* see definition */ #define FLT_RADIX /* see definition */ #define FLT_MANT_DIG /* see definition */ #define DBL_MANT_DIG /* see definition */ #define LDBL_MANT_DIG /* see definition */ #define FLT_DECIMAL_DIG /* see definition */ #define DBL_DECIMAL_DIG /* see definition */ #define LDBL_DECIMAL_DIG /* see definition */ #define DECIMAL_DIG /* see definition */ #define FLT_DIG /* see definition */ #define DBL_DIG /* see definition */ #define LDBL_DIG /* see definition */ #define FLT_MIN_EXP /* see definition */ #define DBL_MIN_EXP /* see definition */ #define LDBL_MIN_EXP /* see definition */ #define FLT_MIN_10_EXP /* see definition */ #define DBL_MIN_10_EXP /* see definition */ #define LDBL_MIN_10_EXP /* see definition */ #define FLT_MAX_EXP /* see definition */ #define DBL_MAX_EXP /* see definition */ #define LDBL_MAX_EXP /* see definition */ #define FLT_MAX_10_EXP /* see definition */ #define DBL_MAX_10_EXP /* see definition */ #define LDBL_MAX_10_EXP /* see definition */ #define FLT_MAX /* see definition */ #define DBL_MAX /* see definition */ #define LDBL_MAX /* see definition */ #define FLT_EPSILON /* see definition */ #define DBL_EPSILON /* see definition */ #define LDBL_EPSILON /* see definition */ #define FLT_MIN /* see definition */ #define DBL_MIN /* see definition */ #define LDBL_MIN /* see definition */ #define FLT_TRUE_MIN /* see definition */ #define DBL_TRUE_MIN /* see definition */ #define LDBL_TRUE_MIN /* see definition */
[edit] See also
C documentation  for Limits of floating-point types