isnormal
From cppreference.com
C
Concurrency support (C11)
Common mathematical functions
Functions
Basic operations
Maximum/minimum operations
(C23)
(C23)
(C23)
(C23)
(C23)
Exponential functions
Power functions
Trigonometric and hyperbolic functions
Nearest integer floating-point
Floating-point manipulation
Narrowing operations
Quantum and quantum exponent
(C23)
(C23)
(C23)
(C23)
Decimal re-encoding functions
(C23)
(C23)
(C23)
(C23)
Total order and payload functions
(C23)
(C23)
(C23)
(C23)
Classification
(C99)
(C23)
(C99)
(C99)
(C99)
isnormal
(C99)
(C99)
(C23)
(C23)
(C99)
(C99)
(C99)
(C99)
(C99)
(C99)
(C23)
(C23)
Error and gamma functions
Types
(C99)(C99)
(C99)(C99)
(C23)(C23)
Macro constants
Special floating-point values
(C99)(C99)(C23)
(C99)(C23)
(C99)(C23)
Arguments and return values
(C99)(C99)
(C99)(C99)(C99)(C99)(C99)
(C23)(C23)
(C23)(C23)(C23)(C23)(C23)
Error handling
(C99)(C99)
(C99)
Fast operation indicators
(C99)(C99)
(C23)(C23)(C23)(C23)
(C23)(C23)(C23)(C23)
(C23)(C23)(C23)(C23)
(C99)(C23)
(C23)(C23)(C23)(C23)
(C23)(C23)(C23)(C23)
(C23)(C23)(C23)(C23)
Defined in header
<math.h>
#define isnormal(arg) /* implementation defined */
(since C99)
Determines if the given floating-point number arg is normal, i.e. is neither zero, subnormal, infinite, nor NaN. The macro returns an integral value.
FLT_EVAL_METHOD is ignored: even if the argument is evaluated with more range and precision than its type, it is first converted to its semantic type, and the classification is based on that.
[edit] Parameters
arg
-
floating-point value
[edit] Return value
Nonzero integral value if arg is normal, 0 otherwise.
[edit] Example
Run this code
#include <float.h> #include <math.h> #include <stdio.h> int main(void) { printf ("isnormal(NAN) = %d\n", isnormal(NAN)); printf ("isnormal(INFINITY) = %d\n", isnormal(INFINITY)); printf ("isnormal(0.0) = %d\n", isnormal(0.0)); printf ("isnormal(DBL_MIN/2.0) = %d\n", isnormal(DBL_MIN / 2.0)); printf ("isnormal(1.0) = %d\n", isnormal(1.0)); }
Output:
isnormal(NAN) = 0 isnormal(INFINITY) = 0 isnormal(0.0) = 0 isnormal(DBL_MIN/2.0) = 0 isnormal(1.0) = 1
[edit] References
- C23 standard (ISO/IEC 9899:2024):
- 7.12.3.5 The isnormal macro (p: TBD)
- C17 standard (ISO/IEC 9899:2018):
- 7.12.3.5 The isnormal macro (p: TBD)
- C11 standard (ISO/IEC 9899:2011):
- 7.12.3.5 The isnormal macro (p: 237)
- C99 standard (ISO/IEC 9899:1999):
- 7.12.3.5 The isnormal macro (p: 217-218)
[edit] See also
C++ documentation for isnormal