TANPI 3CW "12 December 2007" "mathcw-1.00"

Table of contents


NAME

tanpif, tanpi, tanpil, tanpiw, tanpiq, tanpill, tanpidf, tanpid, tanpidl, tanpidll - tangent function

SYNOPSIS

cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ]

#include <mathcw.h>

extern float tanpif (float x);

extern double tanpi (double x);

extern long double tanpil (long double x);

extern __float80 tanpiw (__float80 x);

extern __float128 tanpiq (__float128 x);

extern long_long_double tanpill (long_long_double x);

extern decimal_float tanpidf (decimal_float x);

extern decimal_double tanpid (decimal_double x);

extern decimal_long_double tanpidl (decimal_long_double x);

extern decimal_long_long_double tanpidll (decimal_long_long_double x);

NB: Functions with prototypes containing underscores in type names may be available only with certain extended compilers.


DESCRIPTION

Compute the tangent of x, where the argument is measured in units of pi. Thus, tanpi(x) = tan(pix). Unlike the normal tangent function, the argument is reduced exactly to the interval [-1,+1] by
r = modf(x, NULL).
The function value is then tan(pir).

RETURN VALUES

If the argument is finite, its tangent is returned. Otherwise, a NaN is returned.

ERRORS

If the argument is a NaN, errno is set to EDOM, and the argument is returned. If the argument is +Infinity or -Infinity, errno is set to EDOM, and a quiet NaN is returned.

SEE ALSO

acos(3CW), acosp(3CW), acospi(3CW), asin(3CW), asinp(3CW), asinpi(3CW), atan(3CW), atan2(3CW), atan2p(3CW), atan2pi(3CW), atanp(3CW), atanpi(3CW), cos(3CW), cosp(3CW), cospi(3CW), cotan(3CW), cotanp(3CW), cotanpi(3CW), sin(3CW), sincos(3CW), sincosp(3CW), sincospi(3CW), sinp(3CW), sinpi(3CW), tan(3CW), tanp(3CW).