cacos(3M)

DESCRIPTION

These functions are available only for IA-64.

cacos() returns the complex arccosine of z, in the range of a strip mathematically unbounded along the imaginary axis and in the interval [0,Pi] along the real axis.

Branch cuts are outside the interval [-1,+1] along the real axis.

cacosf() is a float complex version of cacos(); it takes a float complex argument and returns a float complex result.

USAGE

To use these functions, compile with the default -Ae option. Make sure your program includes <complex.h>, and link in the math library by specifying -lm on the compiler or linker command line.

RETURN VALUES

cacos(conj(z)) = conj(cacos(z))

cacos(±0+i0) returns Pi/2-i0.

cacos(±0+iNaN) returns Pi/2+iNaN.

cacos(x+iInf) returns Pi/2-iInf, for finite x.

cacos(x+iNaN) returns NaN+iNaN and optionally raises the invalid floating-point exception, for nonzero finite x.

cacos(-Inf+iy) returns Pi-iInf, for positive-signed finite y.

cacos(+Inf+iy) returns +0-iInf, for positive-signed finite y.

cacos(-Inf+iInf) returns 3Pi/4-iInf.

cacos(+Inf+iInf) returns Pi/4-iInf.

cacos(±Inf+iNaN) returns NaN+-iInf (where the sign of the imaginary part of the result is unspecified).

cacos(NaN+iy) returns NaN+iNaN and optionally raises the invalid floating-point exception, for finite y.

cacos(NaN+iInf) returns NaN-iInf.

cacos(NaN+iNaN) returns NaN+iNaN.

ERRORS

No errors are defined.

SEE ALSO

acos(3M), ccos(3M), complex(5).

STANDARDS CONFORMANCE

cacos(), cacosf(): ISO/IEC C99 (including Annex G, IEC 60559-compatible complex arithmetic)