COSPI 3CW "12 December 2007" "mathcw-1.00"
Table of contents
cospif, cospi, cospil, cospiw, cospiq, cospill, cospidf, cospid, cospidl, cospidll - cosine function
cc [ flags ] -I/usr/local/include file(s) -L/usr/local/lib -lmcw [ ... ]
#include <mathcw.h>
extern float cospif (float x);
extern double cospi (double x);
extern long double cospil (long double x);
extern __float80 cospiw (__float80 x);
extern __float128 cospiq (__float128 x);
extern long_long_double cospill (long_long_double x);
extern decimal_float cospidf (decimal_float x);
extern decimal_double cospid (decimal_double x);
extern decimal_long_double cospidl (decimal_long_double x);
extern decimal_long_long_double cospidll (decimal_long_long_double x);
NB: Functions with prototypes containing underscores in type names
may be available only with certain extended compilers.
Compute the cosine of
x,
where the argument is measured in units of pi. Thus,
cospi(x) = cos(pix).
Unlike the normal cosine function, the argument is reduced
exactly to the interval [-1,+1] by
r = modf(0.5 * x, NULL).
The function value is then cos(pir).
If the argument is finite, its cosine is returned. Otherwise, a NaN
is returned.
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.
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),
cotan(3CW),
cotanp(3CW),
cotanpi(3CW),
sin(3CW),
sincos(3CW),
sincosp(3CW),
sincospi(3CW),
sinp(3CW),
sinpi(3CW),
tan(3CW),
tanp(3CW),
tanpi(3CW).