'\" te
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.TH cacos 3M "12 Jul 2006" "SunOS 5.11" "Mathematical Library Functions"
.SH NAME
cacos, cacosf, cacosl \- complex arc cosine functions
.SH SYNOPSIS
.LP
.nf
c99 [ \fIflag\fR... ] \fIfile\fR... \fB-lm\fR [ \fIlibrary\fR... ]
#include <complex.h>

\fBdouble complex\fR \fBcacos\fR(\fBdouble complex\fR \fIz\fR);
.fi

.LP
.nf
\fBfloat complex\fR \fBcacosf\fR(\fBfloat complex\fR \fIz\fR);
.fi

.LP
.nf
\fBlong double complex\fR \fBcacosl\fR(\fBlong double complex\fR \fIz\fR);
.fi

.SH DESCRIPTION
.sp
.LP
These functions compute the complex arc cosine of \fIz\fR, with branch cuts
outside the interval [ -1, +1 ] along the real axis.
.SH RETURN VALUES
.sp
.LP
These functions return the complex arc cosine value, in the range of a strip
mathematically unbounded along the imaginary axis and in the interval  [ 0, \c
.if n pi\c
.if t \(*p
\c
 ] along the real axis.
.SH ERRORS
.sp
.LP
No errors are defined.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
Interface StabilityStandard
_
MT-LevelMT-Safe
.TE

.SH SEE ALSO
.sp
.LP
\fBccos\fR(3M), \fBcomplex.h\fR(3HEAD), \fBattributes\fR(5), \fBstandards\fR(5)