Guardian Native C Library Calls Reference Manual (G06.29+, H06.08+, J06.03+)

exp2f(3) Guardian Native C Library Calls Reference Manual
NAME
exp2f - Computes the base-2 exponential function for a float value
LIBRARY
H-series and J-series native Guardian processes: $SYSTEM.ZDLLnnn.ZCREDLL
32-bit H-series and J-series OSS processes: /G/system/zdllnnn/zcredll
64-bit H-series and J-series OSS processes: /G/system/zdllnnn/ycredll
SYNOPSIS
#include <math.h>
float exp2f(
float x);
PARAMETERS
x Specifies the power to which the base-2 logarithm is to be raised.
DESCRIPTION
The exp2f() function is a float version of the exp2() function; it takes a float argument and
returns a float result.
The exp2f() function computes the base-2 exponential function of x, defined as 2
x
.
NOTES
This function is implemented only for the IEEE_float floating-point option. Applications using
this function cannot be compiled if the specified floating-point option is Tandem_float.
RETURN VALUES
Upon successful completion, exp2f() returns the value of the base-2 exponential function of x.
If the value of x is positive or negative zero, 1 is returned.
If the value of x is positive infinity, x is returned. If the value of x is negative infinity, positive
zero is returned.
If the value of x is NaN, NaN is returned.
If the correct value would cause overflow, the exp2f() function returns HUGE_VALF and sets
errno to [ERANGE]. If the correct value would cause underflow, the exp2f() function returns a
value of 0.0 (zero) and sets errno to [ERANGE].
ERRORS
If any of the following conditions occurs, the exp2f() function sets errno to the corresponding
value:
[ERANGE] The result would cause underflow or overflow.
RELATED INFORMATION
Functions: cbrt(3), exp(3), exp2(3), exp2l(3), expm1(3), log(3), log2(3), pow(3).
Files: math(4).
STANDARDS CONFORMANCE
This function conforms to the ISO/IEC 9899:1999 standard.
This function conforms to the IEEE Std 1003.1, 2004 Edition.
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