Symbolic Math Constants

The following symbolic constants are available.

Built-in Math Constants

Constant Name Description
MAXFLOAT Value of maximum non-infinite single-precision floating-point number.
HUGE_VALF A positive float constant expression. HUGE_VALF evaluates to +infinity. Used as an error value returned by the built-in math functions.
HUGE_VAL A positive double expression that evaluates to + infinity. Used as an error value returned by the built-in math functions. (Available if the built-in math functions are extended with cl_khr_fp64.)
INFINITY A constant expression of type float representing positive or unsigned infinity.
NAN A constant expression of type float representing a quiet NaN.

Float and Double Math Constants

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 log2e
M_LOG10E_F Value of log10e
M_LN2_F Value of loge2
M_LN10_F Value of loge10
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)

The following constants are available if the built-in math functions are extended with cl_khr_fp64. 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 log2e
M_LOG10E Value of log10e
M_LN2 Value of loge2
M_LN10 Value of loge10
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)

Specification

OpenCL Specification

Also see

Math Functions, Floating Point Pragma, Macros and Limits

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