Guardian Native C Library Calls Reference Manual (G06.28+, H06.04+)

Guardian Native C Library Calls (a - e) cbrt(3)
NAME
cbrt - Computes the cube root of a floating-point number
LIBRARY
G-series native Guardian processes: $SYSTEM.SYSnn.ZCRESRL
G-series native OSS processes: /G/system/sysnn/zcresrl
H-series native Guardian processes: $SYSTEM.ZDLLnnn.ZCREDLL
H-series OSS processes: /G/system/zdllnnn/zcredll
SYNOPSIS
#include <math.h>
double cbrt(
double x);
PARAMETERS
x Is the value whose cube root is to be computed.
DESCRIPTION
The cbrt() function calculates the cube root of x.
The cbrt() 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 (zero) can be either positive or nega-
tive. 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 cbrt() function returns the cube root of the x parameter.
For IEEE floating-point values, if the value of x is NaN, the cbrt() function returns NaN. If the
value of x is positive infinity, the cbrt() function returns positive infinity. If the value of x is
negative infinity, the cbrt() function returns negative infinity.
ERRORS
The cbrt() function does not set errno.
RELATED INFORMATION
Functions: fp_class(3).
STANDARDS CONFORMANCE
The XPG4 Version 2 specification leaves some features to the implementing vendor to define.
The following features are affected in the HP implementation:
• For IEEE floating-point data, this function does not set errno to [EDOM] if the value of
x is NaN.
527192-005 Hewlett-Packard Company 1−31