illumos: manual page: math.h.3head

MATH.H(3HEAD) Headers MATH.H(3HEAD)

NAME

math.h, math - mathematical declarations

SYNOPSIS

#include <math.h>

DESCRIPTION

The <math.h> header includes definitions for the following types:

float_t
A real-floating type at least as wide as float.

double_t
A real-floating type at least as wide as double, and at least
as wide as float_t.

If FLT_EVAL_METHOD equals 0, float_t and double_t are float and double,
respectively. If FLT_EVAL_METHOD equals 1, they are both double. If
FLT_EVAL_METHOD equals 2, they are both be long double. Other values of
FLT_EVAL_METHOD are implementation-defined.

The <math.h> header provides the following constants. The values are of
type double and are accurate within the precision of the double type.

M_E
The base of natural logarithms (e).

M_LOG2E
The base-2 logarithm of e.

M_LOG10E
The base-10 logarithm of e.

M_LN2
The natural logarithm of 2.

M_LN10
The natural logarithm of 10.

M_PI
pi, the ratio of the circumference of a circle to its
diameter.

M_PI_2
pi/2.

M_PI_4
pi/4.

M_1_PI
1/pi

M_2_PI
2/pi

M_2_SQRTPI
2 over the square root of pi

M_SQRT2
The positive square root of 2.

M_SQRT1_2
The positive square root of 1/2.

The <math.h> header defines the following symbolic constants:

MAXFLOAT
The maximum value of a non-infinite single-precision
floating point number.

HUGE_VAL
A positive double expression, not necessarily representable
as a float. Used as an error value returned by the
mathematics library. HUGE_VAL evaluates to +infinity on
systems supporting IEEE Std 754-1985.

HUGE_VALF
A positive float constant expression. Used as an error value
returned by the mathematics library. HUGE_VALF evaluates to
+infinity on systems supporting IEEE Std 754-1985.

HUGE_VALL
A positive long double constant expression. Used as an error
value returned by the mathematics library. HUGE_VALL
evaluates to +infinity on systems supporting IEEE Std
754-1985.

INFINITY
A constant expression of type float representing positive or
unsigned infinity, if available; else a positive constant of
type float that overflows at translation time.

NAN
A constant expression of type float representing a quiet
NaN. This symbolic constant is only defined if the
implementation supports quiet NaNs for the float type.

The following macros are defined for number classification. They
represent the mutually-exclusive kinds of floating-point values. They
expand to integer constant expressions with distinct values

FP_INFINITE
FP_NAN
FP_NORMAL
FP_SUBNORMAL
FP_ZERO

The following optional macros indicate whether the fma() family of
functions are fast compared with direct code:

FP_FAST_FMA
FP_FAST_FMAF
FP_FAST_FMAL

The FP_FAST_FMA macro is defined to indicate that the fma() function
generally executes about as fast as, or faster than, a multiply and an
add of double operands. The other macros have the equivalent meaning for
the float and long double versions.

The following macros expand to integer constant expressions whose values
are returned by ilogb(x) if x is zero or NaN, respectively. The value of
FP_ILOGB0 is either {INT_MIN} or -{INT_MAX}. The value of FP_ILOGBNAN is
either {INT_MAX} or {INT_MIN}.

FP_ILOGB0
FP_ILOGBNAN

The following macros expand to the integer constants 1 and 2,
respectively:

MATH_ERRNO
MATH_ERREXCEPT

The following macro expands to an expression that has type int and the
value MATH_ERREXCEPT:

math_errhandling

The value of the macro math_errhandling is constant for the duration of
the program. If a macro definition is suppressed or a program defines an
identifier with the name math_errhandling, the behavior is undefined.

The <math.h> header defines the following external variable:

extern int signgam;

The <math.h> header defines the structure and constants used by the
matherr(3M) error-handling mechanisms.

ATTRIBUTES

NAME

SYNOPSIS

DESCRIPTION

ATTRIBUTES

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