NAME

       log,_log2,_log10,_log1p,_logb - Logarithm functions.

       gentype log(gentype );

       gentype log2(gentype );

       gentype log10(gentype );

       gentype log1p(gentype x);

       gentype logb(gentype x);

       gentype half_log(gentype x);

       gentype half_log2(gentype x);

       gentype half_log10(gentype x);

       gentype native_log(gentype x);

       gentype native_log2(gentype x);

       gentype native_log10(gentype x);

DESCRIPTION

       log computes natural logarithm.

       log2 computes a base 2 logarithm.

       log10 computes a base 10 logarithm.

       log1p computes loge(1.0 + x).

       logb computes the exponent of x, which is the integral part of logr |x|.

       half_log computes natural logarithm.

       half_log2 computes a base 2 logarithm.

       half_log10 computes a base 10 logarithm.

       native_log computes natural logarithm over an implementation-defined range. The maximum
       error is implementation-defined.

       native_log2 computes a base 2 logarithm over an implementation-defined range. The maximum
       error is implementation-defined.

       native_log10 computes a base 10 logarithm over an implementation-defined range. The
       maximum error is implementation-defined.

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 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.

       Functions with the half_ prefix are implemented with a minimum of 10-bits of accuracy i.e.
       an ULP value less than or equal to 8192 ulp.

       Functions with the native__ prefix may map to one or more native device instructions and
       will typically have better performance compared to the corresponding functions (without
       the native__ prefix). The accuracy (and in some cases the input range(s)) of these
       functions is implementation-defined.

SPECIFICATION

       OpenCL Specification[1]

SEE ALSO

       mathFunctions(3clc)

AUTHORS

       The Khronos Group

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