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

Guardian Native C Library Calls (n - r) pow(3)
• If the value of x is positive or negative 0.0 (zero) and the value of y is an odd integral
value greater than 0.0 (zero), positive or negative 0.0 (zero) is returned.
• If the value of x is positive or negative 0.0 (zero) and the value of y is not an odd integral
value but is greater than 0.0 (zero), positive 0.0 (zero) is returned.
ERRORS
If any of the following conditions occurs, the pow() function sets errno to the corresponding
value:
[EDOM] One of the following conditions exists:
• The value of x is negative and the value of y is nonintegral.
• The value of x is 0.0 (zero) and the value of y is negative.
[ERANGE] The value to be returned would have caused an underflow or an overflow.
RELATED INFORMATION
Functions: exp(3), fp_class(3), isnan(3), log(3), log10(3), sinh(3).
STANDARDS CONFORMANCE
This function conforms to the XPG4 Version 2 specification with extensions when used for IEEE
floating-point format data. This function conforms to the XPG4 Version 2 specification without
extensions when used for Tandem floating-point data.
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
y is NaN.
• The errno value of [EDOM] is used instead of [ERANGE] when the value of x is 0.0
(zero) and the value of y is negative.
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