modf

Decompose a floating-point number.

gentype modf ( gentype x,
  __global gentype *iptr)
gentype modf ( gentype x,
  __local gentype *iptr)
gentype modf ( gentype x,
  __private gentype *iptr)

Description

Decompose a floating-point number. The modf function breaks the argument x into integral and fractional parts, each of which has the same sign as the argument. It stores the integral part in the object pointed to by iptr.

Notes

modf behaves as though implemented by:


          gentype modf ( gentype value, gentype *iptr )
          {
                    *iptr = truncvalue );
                    return copysignisinfvalue ) ? 0.0 : value -  *iptrvalue );
          }

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, 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.

Specification

OpenCL Specification

Also see

Math Functions

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