HP-UX Reference (11i v2 04/09) - 3 Library Functions A-M (vol 6)

a
atan2(3M) atan2(3M)
If y is ±INFINITY and x is finite,
atan2() returns ±Pi/2 respectively.
If y is ±INFINITY and x is −INFINITY,
atan2() returns ±3*Pi/4 respectively.
If y is ±INFINITY and x is +INFINITY,
atan2() returns ±Pi/4 respectively.
If x or y is NaN,
atan2()
returns NaN.
Whether
atan2() raises the inexact exception is unspecified.
ERRORS
No errors are defined.
SEE ALSO
acos(3M), asin(3M), atan(3M), atan2d(3M), carg(3M), cos(3M), sin(3M), tan(3M), math(5).
STANDARDS CONFORMANCE
atan2() : SVID3, XPG4.2, ANSI C, ISO/IEC C99 (including Annex F, ‘‘IEC 60559 floating-point arith-
metic’’)
atan2f(), atan2l() : ISO/IEC C99 (including Annex F, ‘‘IEC 60559 floating-point arithmetic’’)
Section 3−−42 Hewlett-Packard Company − 2 − HP-UX 11i Version 2: September 2004