The following symbolic constants are available.
Builtin Math Constants
The following symbolic constants are available.
Their values are of type float
and are accurate within the precision of a single precision floatingpoint number.
Constant Name  Description 

MAXFLOAT 
Value of maximum noninfinite singleprecision floatingpoint number. 
HUGE_VALF 
A positive float constant expression.

INFINITY 
A constant expression of type 
NAN 
A constant expression of type 
If double precision is supported by the device, the following symbolic constant will also be available:
Constant Name  Description 

HUGE_VAL 
A positive double constant expression.

The following constants are also available.
They are of type float
and are accurate within the precision of the float
type.
Constant Name  Description 

M_E_F 
Value of e 
M_LOG2E_F 
Value of log_{2}e 
M_LOG10E_F 
Value of log_{10}e 
M_LN2_F 
Value of log_{e}2 
M_LN10_F 
Value of log_{e}10 
M_PI_F 
Value of pi 
M_PI_2_F 
Value of pi / 2 
M_PI_4_F 
Value of pi / 4 
M_1_PI_F 
Value of 1 / pi 
M_2_PI_F 
Value of 2 / pi 
M_2_SQRTPI_F 
Value of 2 / (square root of pi) 
M_SQRT2_F 
Value of square root of 2 
M_SQRT1_2_F 
Value of 1 / (square root of 2) 
If double precision is supported by the device, the following macros and constants are also available.
They are of type double
and are accurate within the precision of the double
type.
Constant Name  Description 

M_E 
Value of e 
M_LOG2E 
Value of log_{2}e 
M_LOG10E 
Value of log_{10}e 
M_LN2 
Value of log_{e}2 
M_LN10 
Value of log_{e}10 
M_PI 
Value of pi 
M_PI_2 
Value of pi / 2 
M_PI_4 
Value of pi / 4 
M_1_PI 
Value of 1 / pi 
M_2_PI 
Value of 2 / pi 
M_2_SQRTPI 
Value of 2 / (square root of pi) 
M_SQRT2 
Value of square root of 2 
M_SQRT1_2 
Value of 1 / (square root of 2) 
The following constants are also available.
They are of type half
and are accurate within the precision of the half
type.
An application that wants to use half
and halfn
types will need to include the #pragma OPENCL EXTENSION cl_khr_fp16 : enable
directive.
Constant  Description 

M_E_H 
Value of e 
M_LOG2E_H 
Value of log_{2}e 
M_LOG10E_H 
Value of log_{10}e 
M_LN2_H 
Value of log_{e}2 
M_LN10_H 
Value of log_{e}10 
M_PI_H 
Value of pi 
M_PI_2_H 
Value of pi / 2 
M_PI_4_H 
Value of pi / 4 
M_1_PI_H 
Value of 1 / pi 
M_2_PI_H 
Value of 2 / pi 
M_2_SQRTPI_H 
Value of 2 / (square root of pi) 
M_SQRT2_H 
Value of square root of 2 
M_SQRT1_2_H 
Value of 1 / (square root of 2) 