Log gamma functions.
gentype lgamma(gentype x); floatn lgamma_r(floatn x, __global intn *signp); floatn lgamma_r(floatn x, __local intn *signp); floatn lgamma_r(floatn x, __private intn *signp); float lgamma_r(float x, __global int *signp); float lgamma_r(float x, __local int *signp); float lgamma_r(float x, __private int *signp); doublen lgamma_r(doublen x, __global intn *signp); doublen lgamma_r(doublen x, __local intn *signp); doublen lgamma_r(doublen x, __private intn *signp); double lgamma_r(double x, __global int *signp); double lgamma_r(double x, __local int *signp); double lgamma_r(double x, __private int *signp); halfn lgamma_r(halfn x, __global intn *signp); halfn lgamma_r(halfn x, __local intn *signp); halfn lgamma_r(halfn x, __private intn *signp); half lgamma_r(half x, __global int *signp); half lgamma_r(half x, __local int *signp); half lgamma_r(half x, __private int *signp);
Returns the natural logarithm of the absolute value of the gamma function. The sign of the gamma function is returned in the signp argument of the lgamma_r.
An application that wants to use half and halfn types will need to include the #pragma OPENCL EXTENSION cl_khr_fp16(3clc) : enable directive. If extended with cl_khr_fp16(3clc), generic type name gentype also includes half and half{2|3|4|8|16}.
The vector versions of the math functions operate component-wise. The description is per-component.
The built-in math functions are not affected by the prevailing rounding mode in the calling environment, and always return the same value as they would if called with the round to nearest even rounding mode.
The built-in math functions take scalar or vector arguments. For any specific use of these function, the actual type has to be the same for all arguments and the return type unless otherwise specified.
The generic type name gentype is used to indicate that the function can take float, float2, float3, float4, float8, float16, double, double2, double3, double4, double8, or double16 as the type for the arguments.
If extended with cl_khr_fp16(3clc), generic type name gentype may indicate half and half{2|3|4|8|16} as arguments and return values.
The generic type name gentypef is used to indicate that the function can take float, float2, float3, float4, float8, or float16 as the type for the arguments.
The generic type name gentyped is used to indicate that the function can take double, double2, double3, double4, double8, or double16 as the type for the arguments.
\m[blue]OpenCL Specification\m[]\s-2\u[1]\d\s+2
mathFunctions(3clc)
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OpenCL Specification
page 244, section 6.12.2 - Math Functions