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

acoshl(3) Guardian Native C Library Calls Reference Manual
NAME
acoshl - Computes the inverse hyperbolic cosine function for a long double 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>
long double acoshl(
long double x);
PARAMETERS
x Is the long double value for which the inverse hyperbolic cosine function is to be
computed.
DESCRIPTION
The acoshl() function is a long double version of the acosh() function; it takes a long double
argument and returns a long double result.
The acoshl() function computes the inverse hyperbolic cosine of x.
The acoshl() function can be called only by native processes.
NOTES
This function supports both IEEE Std 754-1985 floating-point and Tandem floating-point values.
IEEE values can include NaN and infinity, and the sign of 0.0 (zero) can be either positive or
negative. Refer to the fp_class(3) reference page for a description of IEEE value classes.
Guardian functions are available to convert between floating-point formats. Refer to the Guar-
dian Programmer’s Guide for a discussion of floating-point conversions.
RETURN VALUES
The acoshl() function returns the inverse hyperbolic cosine of the x parameter.
For IEEE floating-point values, when the value of x is NaN, the acoshl() function returns NaN.
When the value of x is positive infinity, the acoshl() function returns positive infinity. When the
value of x is less than 1.0, the acoshl() function returns NaN and sets errno to [EDOM]. When
the value of x is negative infinity, the acoshl() function returns NaN and sets errno to [EDOM].
For Tandem floating-point values, when the value of x is less than 1.0, the acoshl() function
returns -HUGE_VALL and sets errno to [EDOM].
ERRORS
If the following condition occurs, the acoshl() function sets errno to the corresponding value:
[EDOM] The value of the x parameter is less than 1.0 or, for IEEE floating-point values,
the value of x is negative infinity.
RELATED INFORMATION
Functions: acosh(3), acoshf(3), asinh(3), atanh(3), cacosh(3), cosh(3), fp_class(3), isnan(3).
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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