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If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner] .TH MATH.H 3HEAD "Aug 11, 2004" .SH NAME math.h, math \- mathematical declarations .SH SYNOPSIS .LP .nf \fB#include <math.h>\fR .fi .SH DESCRIPTION .sp .LP The <\fBmath.h\fR> header includes definitions for the following types: .sp .ne 2 .na \fB\fBfloat_t\fR\fR .ad .RS 12n A real-floating type at least as wide as \fBfloat\fR. .RE .sp .ne 2 .na \fB\fBdouble_t\fR\fR .ad .RS 12n A real-floating type at least as wide as \fBdouble\fR, and at least as wide as \fBfloat_t\fR. .RE .sp .LP If \fBFLT_EVAL_METHOD\fR equals 0, \fBfloat_t\fR and \fBdouble_t\fR are \fBfloat\fR and \fBdouble\fR, respectively. If \fBFLT_EVAL_METHOD\fR equals 1, they are both \fBdouble\fR. If \fBFLT_EVAL_METHOD\fR equals 2, they are both be \fBlong double\fR. Other values of \fBFLT_EVAL_METHOD\fR are implementation-defined. .sp .LP The <\fBmath.h\fR> header provides the following constants. The values are of type \fBdouble\fR and are accurate within the precision of the \fBdouble\fR type. .sp .ne 2 .na \fB\fBM_E\fR\fR .ad .RS 14n The base of natural logarithms (\fIe\fR). .RE .sp .ne 2 .na \fB\fBM_LOG2E\fR\fR .ad .RS 14n The base-2 logarithm of \fIe\fR. .RE .sp .ne 2 .na \fB\fBM_LOG10E\fR\fR .ad .RS 14n The base-10 logarithm of \fIe\fR. .RE .sp .ne 2 .na \fB\fBM_LN2\fR\fR .ad .RS 14n The natural logarithm of 2. .RE .sp .ne 2 .na \fB\fBM_LN10\fR\fR .ad .RS 14n The natural logarithm of 10. .RE .sp .ne 2 .na \fB\fBM_PI\fR\fR .ad .RS 14n \c .if n pi\c .if t \(*p \c , the ratio of the circumference of a circle to its diameter. .RE .sp .ne 2 .na \fB\fBM_PI_2\fR\fR .ad .RS 14n \c .if n pi\c .if t \(*p \c /2. .RE .sp .ne 2 .na \fB\fBM_PI_4\fR\fR .ad .RS 14n \c .if n pi\c .if t \(*p \c /4. .RE .sp .ne 2 .na \fB\fBM_1_PI\fR\fR .ad .RS 14n 1/\c .if n pi\c .if t \(*p \c . .RE .sp .ne 2 .na \fB\fBM_2_PI\fR\fR .ad .RS 14n 2/\c .if n pi\c .if t \(*p \c . .RE .sp .ne 2 .na \fB\fBM_2_SQRTPI\fR\fR .ad .RS 14n 2 over the square root of \c .if n pi\c .if t \(*p \c . .RE .sp .ne 2 .na \fB\fBM_SQRT2\fR\fR .ad .RS 14n The positive square root of 2. .RE .sp .ne 2 .na \fB\fBM_SQRT1_2\fR\fR .ad .RS 14n The positive square root of 1/2. .RE .sp .LP The <\fBmath.h\fR> header defines the following symbolic constants: .sp .ne 2 .na \fB\fBMAXFLOAT\fR\fR .ad .RS 13n The maximum value of a non-infinite single-precision floating point number. .RE .sp .ne 2 .na \fB\fBHUGE_VAL\fR\fR .ad .RS 13n A positive \fBdouble\fR expression, not necessarily representable as a float. Used as an error value returned by the mathematics library. \fBHUGE_VAL\fR evaluates to +infinity on systems supporting IEEE Std 754-1985. .RE .sp .ne 2 .na \fB\fBHUGE_VALF\fR\fR .ad .RS 13n A positive \fBfloat\fR constant expression. Used as an error value returned by the mathematics library. \fBHUGE_VALF\fR evaluates to +infinity on systems supporting IEEE Std 754-1985. .RE .sp .ne 2 .na \fB\fBHUGE_VALL\fR\fR .ad .RS 13n A positive \fBlong double\fR constant expression. Used as an error value returned by the mathematics library. \fBHUGE_VALL\fR evaluates to +infinity on systems supporting IEEE Std 754-1985. .RE .sp .ne 2 .na \fB\fBINFINITY\fR\fR .ad .RS 13n A constant expression of type \fBfloat\fR representing positive or unsigned infinity, if available; else a positive constant of type \fBfloat\fR that overflows at translation time. .RE .sp .ne 2 .na \fB\fBNAN\fR\fR .ad .RS 13n A constant expression of type float representing a quiet NaN. This symbolic constant is only defined if the implementation supports quiet NaNs for the \fBfloat\fR type. .RE .sp .LP 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 .sp .in +2 .nf FP_INFINITE FP_NAN FP_NORMAL FP_SUBNORMAL FP_ZERO .fi .in -2 .sp .LP The following optional macros indicate whether the \fBfma()\fR family of functions are fast compared with direct code: .sp .in +2 .nf FP_FAST_FMA FP_FAST_FMAF FP_FAST_FMAL .fi .in -2 .sp .LP The \fBFP_FAST_FMA\fR macro is defined to indicate that the \fBfma()\fR function generally executes about as fast as, or faster than, a multiply and an add of \fBdouble\fR operands. The other macros have the equivalent meaning for the \fBfloat\fR and \fBlong double\fR versions. .sp .LP The following macros expand to integer constant expressions whose values are returned by \fBilogb\fR(\fIx\fR) if \fIx\fR is zero or NaN, respectively. The value of \fBFP_ILOGB0\fR is either {\fBINT_MIN\fR} or -{\fBINT_MAX\fR}. The value of \fBFP_ILOGBNAN\fR is either {\fBINT_MAX\fR} or {\fBINT_MIN\fR}. .sp .in +2 .nf FP_ILOGB0 FP_ILOGBNAN .fi .in -2 .sp .LP The following macros expand to the integer constants 1 and 2, respectively: .sp .in +2 .nf MATH_ERRNO MATH_ERREXCEPT .fi .in -2 .sp .LP The following macro expands to an expression that has type \fBint\fR and the value \fBMATH_ERREXCEPT\fR: .sp .in +2 .nf math_errhandling .fi .in -2 .sp .LP The value of the macro \fBmath_errhandling\fR is constant for the duration of the program. If a macro definition is suppressed or a program defines an identifier with the name \fBmath_errhandling\fR, the behavior is undefined. .sp .LP The <\fBmath.h\fR> header defines he following external variable: .sp .in +2 .nf extern int signgam; .fi .in -2 .sp .LP The <\fBmath.h\fR> header defines the structure and constants used by the \fBmatherr\fR(3M) error-handling mechanisms. .SH ATTRIBUTES .sp .LP See \fBattributes\fR(5) for descriptions of the following attributes: .sp .sp .TS box; c | c l | l . ATTRIBUTE TYPE ATTRIBUTE VALUE _ Interface Stability Standard .TE .SH SEE ALSO .sp .LP \fBIntro\fR(3), \fBfenv.h\fR(3HEAD), \fBlibm\fR(3LIB), \fBlimits.h\fR(3HEAD), \fBmatherr\fR(3M), \fBattributes\fR(5), \fBstandards\fR(5)