Provided by: opencl-1.2-man-doc_1.0~svn22836-1.1_all

**NAME**

lgamma,_lgamma_r - Log gamma functions.gentypelgamma(gentypex);floatnlgamma_r(floatnx,__globalintn*signp);floatnlgamma_r(floatnx,__localintn*signp);floatnlgamma_r(floatnx,__privateintn*signp);floatlgamma_r(floatx,__globalint*signp);floatlgamma_r(floatx,__localint*signp);floatlgamma_r(floatx,__privateint*signp);doublenlgamma_r(doublenx,__globalintn*signp);doublenlgamma_r(doublenx,__localintn*signp);doublenlgamma_r(doublenx,__privateintn*signp);doublelgamma_r(doublex,__globalint*signp);doublelgamma_r(doublex,__localint*signp);doublelgamma_r(doublex,__privateint*signp);halfnlgamma_r(halfnx,__globalintn*signp);halfnlgamma_r(halfnx,__localintn*signp);halfnlgamma_r(halfnx,__privateintn*signp);halflgamma_r(halfx,__globalint*signp);halflgamma_r(halfx,__localint*signp);halflgamma_r(halfx,__privateint*signp);

**DESCRIPTION**

Returns the natural logarithm of the absolute value of the gamma function. The sign of the gamma function is returned in thesignpargument of thelgamma_r. An application that wants to usehalfandhalfntypes will need to include the #pragma OPENCL EXTENSIONcl_khr_fp16(3clc) : enable directive. If extended withcl_khr_fp16(3clc), generic type namegentypealso includeshalfandhalf{2|3|4|8|16}.

**NOTES**

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 namegentypeis used to indicate that the function can takefloat,float2,float3,float4,float8,float16,double,double2,double3,double4,double8, ordouble16as the type for the arguments. If extended withcl_khr_fp16(3clc), generic type namegentypemay indicatehalfandhalf{2|3|4|8|16}as arguments and return values. The generic type namegentypefis used to indicate that the function can takefloat,float2,float3,float4,float8, orfloat16as the type for the arguments. The generic type namegentypedis used to indicate that the function can takedouble,double2,double3,double4,double8, ordouble16as the type for the arguments.

**SPECIFICATION**

OpenCLSpecification[1]

**SEE** **ALSO**

mathFunctions(3clc)

**AUTHORS**

TheKhronosGroup

**COPYRIGHT**

Copyright © 2007-2011 The Khronos Group Inc. Permission is hereby granted, free of charge, to any person obtaining a copy of this software and/or associated documentation files (the "Materials"), to deal in the Materials without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Materials, and to permit persons to whom the Materials are furnished to do so, subject to the condition that this copyright notice and permission notice shall be included in all copies or substantial portions of the Materials.

**NOTES**

1. OpenCL Specification page 244, section 6.12.2 - Math Functions