logbf4

NAME

logbf4 - return exponents of float elements

SYNOPSIS

Procedure call syntax:

#include <simdmath.h>

vector float logbf4(vector float x);

Link with -lsimdmath

Inline call syntax:

#include <simdmath.h>

#include <logbf4.h>

vector float _logbf4(vector float x);

Parameters
x	input vector

DESCRIPTION

The logbf4 function determines an integer exponent exp and a fraction frac that represent the value of a finite element of x.

RETURN VALUE

The function logbf4 returns a float vector in which each element is defined as the exponent of the corresponding element of x expressed as a floating-point value, such that:

$x=frac*exp^FLT_RADIX$
|frac| is in the interval [1, FLT_RADIX)
If an element of x is negative, the corresponding element of the result is undefined.

For the logbf4 function on the SPU:

if an element of x is 0 the result is undefined.

ENVIRONMENT

SPU and PPU

CONFORMING TO

SIMD Math library specification for the Cell Broadband Engine™ Architecture.

NOTES

Basis

ISO9899 (C99) logb functions.